travis: fix llvm build

[skip bamboo]

travis: add gpg keys

[skip bamboo]

travis: fix package ppa

[skip bamboo]

travis: try fixing clang dependencies

[skip bamboo]

compiler: fix llvm merge

[skip bamboo]

travis: allow a larger timeout

[skip bamboo]

travis: fix flags

[skip bamboo]

travis: fix wrong configure command

[skip bamboo]

travis: use flags consistently

[skip bamboo]

travis: fix env var conflict

travis: reinforce that it only deploys on master

[skip ci]

travis: update travis setup a bit

[skip bamboo]

travis: fix travis post-deploy setup

[skip bamboo]

travis: use a ruby script to clean up old releases

[skip bamboo]

travis: config fixes + lint

[skip bamboo]

travis: fix format error

[skip bamboo]

traivs: use travis build number instead of id

[skip bamboo]

travis: try if it removes old auto-deploys

[skip bamboo]

travis: try to fix file in build

[skip bamboo]

travis: tags also not defined

[skip bamboo]

travis: release v2 doesn't have script flag

[skip bamboo]

travis: tweaks

[skip bamboo]

travis: try skip script

[skip bamboo]

travis: test jobs and stages

[skip bamboo]

travis: more deployment experiments

[skip bamboo]

travis: just for testing

[skip bamboo]

travis: tweak not. and release

[skip bamboo]

travis: small tweaks to fix deployment and notification

[skip bamboo]

travis: token setup changes

[skip bamboo]

travis: re-enable tests

travis: disable some tests

[skip bamboo]

travis: try github releases deployment

[skip bamboo]

ci: adapt to new cabal

travis: add ghc-8.8.3 matrix

compiler.dargent: WIP - typecheck for layout polymorphism

- have typecheck working for some basic cases
- change core lang to allow layout args
- introduce TLApp to surface syntax

[skip lemma]

compiler.dargent: WIP - progress on typechecking

- also modify travis config, it should be able to build binary now

[skip lemma]

travis: allow ghc-8.2.1 to fail

.. due to its faulty dependency.
[skip lemma]

travis: give travis a larger timeout

[skip lemma]

travis: add a wait and enable arrays

[skip lemma]

travis: switch it off on this branch

[skip lemma]

traivs: enable one cabal test

[skip lemma]

travis: set up travis for the new testing script

[skip lemma]

tests: migrate to new testing script (partially)

also see #350 for what's missing
[skip lemma]

proof: update proofs to Isabelle 2019 / AutoCorres 1.6

Fix Travis CICD failures (#294)

* Fixed problem with documentation not building, tests not pasing

compiler: add ghc-8.6.5 support

[skip lemma]

travis: add gc-8.6.4 test

[skip lemma]

travis: add ghc-8.6.3

[skip lemma]

autocorres: make autocorres a prerequisite

tests: fix antiquote tests

[skip lemma]

ci: rename channel name

[skip lemma]

compiler: now support ghc-8.6.[12]

[skip lemma]

compiler: support more ghc versions

compiler:
* add new build config files
* relax constraint on microlens
* add matrix for ghc-8.6.[12] and ghc-8.4.4
* update docs.

travis:
* allow 8.6 to fail,
* using new cabal version (2.2)
* once graph-wrapper-0.2.5.2 is online, it should work

[skip lemma]

travis: fix compiler values to generate urls properly

[skip lemma]

travis: flags in more places

[skip lemma]

travis: enable all compiler flags

[skip lemma]

travis: also compile haddock

change the travis slack room

ci: stop notifying hipchat. we have slack already.

[skip ci]

travis: also run the compiler on the fses

[skip ci]

notify cogent club slack.

travis: fix z3 cache-hit actions

add ghc-8.4.3 support and update README files

compiler: largely improve coherence btw parser and pp

compiler: update scripts accordingly

travis: use fixed build plan and cache z3

travis: install z3

[skip lemma]

compiler: fix (<>) for older ghc

[skip ci][skip lemma]

ci: update travis setup

[skip lemma]

compiler: try to drop ghc-8.0 and add ghc-8.4

[skip lemma]

compiler: raise cabal version constraint

[skip lemma]

compiler: try out fixed build plans

[skip lemma]

travis: block this branch

compiler: improve testsuite and scripts

now we have a pass_flags_* or fail_flags_* pattern
that we can automatically test for compiler flags

ci: try to catch up with travis image update

https://docs.travis-ci.com/user/build-environment-updates/2017-12-12/

ci: enable ci to get more feedback

ci: exclude this branch

ci: try a different build env with more mem

eventually I can see the green ticks again! :)

ci: enable test for ghc-8.2.2 release

[skip ci]

ci: revert last commit. see travis-ci/#5071

ci: add another wait instruction

compiler: add support for ghc-8.2.1

* use --force-reinstalls flag

* require cabal-install-1.24 or above

* use new cabal features and enforce some package versions

* enforce pandoc's version

ci: try travis_wait

compiler: support GHC-8.0.2

[skip ci]

ci: try more versions of ghc

regression: lemma and travis cover most tests (minus huge proofs)

* add some isabelle related tests back to lemma-regression
* update libgum typecheck test
* fix isabelle tests
* fix bilby build (fail due to kernel compatibility)
* other misc fixes to test script

license: fix some licenses and use upstream cancellatives

travis: cache the entire sandbox

* use multi-ghc-travis template
* also add file systems builds in the CI
* tried the new nix-style cabal: DOES'T WORK
- it needs all files added to the .cabal file,
- which means for us all libgum
* tried without a sandbox: DOESN'T WORK
- we need to deal with isa-parser separately and
- I don't see a clean way of doing it
* use multiline syntax in the yml file
* make ghc-8.0.2 allow_failure, it currently fails
due to upstream problems
* use jobs: 2 in cabal.config file
* fix directory due to impl reorg

[impl] Reorganise impl directory.

We currently have all our filesystem implementation in `impl` directory. This
patch moves all the implementations into `impl/fs` directory. This makes for
better organisation of the source tree when we eventually have `impl/net`,
for network implementations in `Cogent`.

travis: update yaml script

* remove ghc head env, which never passes
* make each test step really tests something

[impl/fs] Fix ext2 and bilby build issues.

We don't want to build the kernel module(yet) since travis container doesn't
have the kernel headers that are required to build the kernel module. So what
we do is just check if the C code is generated successfully by the Cogent
compiler.

We also encountered a really interesting issue as highlighted in this[1]
stackoverflow post. So we run the initial pass of the `cpp` (from within Cogent)
in the `c99` mode and then when actually building the kernel module we use `cpp`
in `gnu99` mode. Please read the stackoverflow post for more details.

[1] - http://stackoverflow.com/questions/19210935/why-does-the-c-preprocessor-interpret-the-word-linux-as-the-constant-1

ci: add fs builds to ci

ext2 and bilby are not compiling for some reason

examples: add them to travis

[CI] add travis hipchat notification

[CI] Use travis on github for build and sanity.

This commit adds a .travis.yml to the repo. I've also enabled `Travis`
on the `NICTA/cogent` repo and configured it to get travis working for
both `merges` and `pull requests`.
There might be some minor issues still, which I intend to iron out over
the next few days.