rose metadata-check: remove gtk dependence.

This removes the gtk library dependence from
rose metadata-check and the test-battery tests
for it. The importing of widgets and macros
is now via a function in rose.resource.
Added emacs syntax highlighting mode file
Merge pull request #1099 from benfitzpatrick/less-gtk-dependence

rose metadata-check: remove gtk dependence.
Update to fix andrew's suggestion and a few other tweaks
Merge pull request #1100 from stevewardle/emacs_syntax_highlighting

Added emacs syntax highlighting mode file