A few short docstrings in examples for issue #1414

In the spirit of encouraging docstrings in tests...
Add link to flymake-cursor.el in Emacs dev docs
Update matchsep.rst

This PR adds the missing distance parameters in a coordinate matching example.
One slight tweak to the changelog formatting
Preparing release 0.4
Back to development: 0.5
Adding skeletons to changelog for next releases.
Merge pull request #2742 from larrybradley/patch-1

Update matchsep.rst
Merge pull request #2728 from jehturner/patch-1

A few short docstrings in examples for issue #1414
Merge pull request #2722 from jeanconn/add_flymake_cursor

Add link to flymake-cursor.el in Emacs dev docs
Added entry for misc doc updates to changelog
Fix memory leak in WCS reported in #2754
Add changes entry.