Update dates in COPYRIGHT notice

Tidy up RISC-V work on graph decompiler

Update COPYRIGHT dates and CONTRIBUTORS list

Early date of 1985 justified by comment from Tom Melham at head of
src/unwind/unwindLib.sml. Extra contributors added while grepping for
1980s dates in source tree. Jeff Joyce from Tamarack example, Paul
Loewenstein from Conv.sml.

Tidy up copyright documentation

- Move some information out of file headers into various files in
doc/copyrights.
- Reinstate a LICENSE file for examples/muddy (which is LGPL).
- Identify code taken directly from Poly/ML implementation in
tools-poly/holrepl.ML

See github discussion at

https://github.com/HOL-Theorem-Prover/HOL/issues/559

for more on this.

Closes #559

Update copyright notice to have 2017 as the date

Add CONTRIBUTORS list; modify COPYRIGHT

I've added a CONTRIBUTORS list that I hope is fairly comprehensive.
I've derived it from the list of acknowledgements in the Manual, and
from an inspection of our git history.

I've also modified the COPYRIGHT to simply assert ownership by the
CONTRIBUTORS. As I've commented in the past, it may be simpler to try
to assert that it is all simply in the public domain.

Update COPYRIGHT notice's years to include 2014.

I dislike claiming ownership like this; perhaps we should just put the
source code into the public domain outright.

Update COPYRIGHT to extend into 2013

Update copyright date to extend to 2012.

Update copyright date to extend to 2011.

Fix to bug spotted by Anthony, whereby the induction
theorem for functions defined by pattern-matching
on literals was failing to be proved. Misc.
simplifications to TFL code plus adding "trypluck" to Lib.

Update some legalese.

Changing the years.

Remove a last mention of Sunrise.

Another year to add to the COPYRIGHT notice.

Bumped up the year.

top-level tweaking.

Revised this in light of the presence of various "alien bodies" within
the core distribution.

New copyright notice, being essentially the BSD licence from
http://www.opensource.org/licenses/bsd-license.html
I have written "copyright holders and contributors" in the place of
<ORGANIZATION> in the template.

Added the year 2001.

Y2Kopyright, including mn200.

Initial revision