Fix bug in emacs mode's handling of open thyname.

Problem arose if the thyname included the string "_fun_".
Thanks to Magnus for the bug report.

You will need to do a fresh ML < tools/smart-configure.sml
to get the new version of the Emacs mode created.

Mention space-wastage bug in Overload in release notes.

Description of ARM_security_properties example for the release notes

Insert links to previous releases in (some) release notes files

Mention bug fixed in 730f9a26a in release notes.

Also add regression test for this bug in src/real.

Mention bug fixed in bba61edf in release notes.

Record fix of new_type_definition problem reported by Rob Arthan.

Change release notes' colour of <code> and <pre> elements to dark green

This makes them more distinct from the standard dark blue that is used
to indicate "visited link".

Add a bunch of Github cross-references to release notes.

Mention fix of bug #115 in the release notes.

Document the suffices_by tactic in the release notes.

(See 97ce3c4 for the commit adding suffices_by.)

Mention parsing example in release notes.

Mention recursive cleaning with -r option in release notes.

New goalstack pretty-printing trace & rationalise goalstack trace names

New trace prints a count of the sub-goals at the end of the stack.
This saves the user from having to scroll back over the several
hundred goals they've just generated to find out the number.

Document HINT_EXISTS_TAC and pattern-matching improvements in release notes.

Document feature of independent function parameters for Define.

This closes #112.

(I have checked everything up to -selftest 2 as well as
examples/machine-code.)

Document the change to MEM in the release notes.

Document bug-fix for array-type type abbreviations in the release notes.

Minor wording improvement in the release notes about case-const-arg-flip.

More documentation about the case-const arg-flip change.

Documentation for the case-constant argument flip change.

This is progress with github issue #97.