Revise bundle development bundle

Made the Require Support File (sup⇥) and TextMate Variable (env⇥) snippets use pop-up menus.

Removed “Show Changes” which was for subversion.
Snippet to specify required TextMate version in commit message
Fix "Show Scope" command to include the left scope

The left-hand scope is represented by the `TM_SCOPE_LEFT` environment variable, not `TM_LEFT_SCOPE`, meaning that the left scope never actually showed up.
Point to ruby 1.8 shim

Using a shim allows us to catch when 1.8 of ruby is not present and provide other options.

#ignore
Do not require rubygems (not available via ruby 1.8 on Yosemite)

I also removed the other unused (and commented) includes.
Add grammar for individual scopes

To be expanded in the future to support scope selectors.
Use scope grammar for language grammars
Merge branch 'master' of http://github.com/textmate/bundle-development.tmbundle

# By Allan Odgaard (3) and others
# Via Michael Sheets
* 'master' of http://github.com/textmate/bundle-development.tmbundle:
  Use scope grammar for language grammars
  Add grammar for individual scopes
  Do not require rubygems (not available via ruby 1.8 on Yosemite)
  Point to ruby 1.8 shim
  Fix "Show Scope" command to include the left scope
  Snippet to specify required TextMate version in commit message
  Revise bundle development bundle