Update documentation of suggest_gems_from_name
Remove underscores and hyphens when finding suggestions
If rdoc or ri were installed, provide guidance on how to use them, and how to not install them in the future.
Add MacRuby to the list of special cases for platforms
Add some tests to make sure MacRuby and Gem::Platform get along
Replace usage of the term "spermy" with "approximate".

* The "spermy" or "twiddle wakka" operator (~>) is similar to the
  greater-equal-then (>=) version operator, except that it matches
  families of versions. This version operator also uses a Tilde character,
  which is commonly used to denote approximate values
  (See definition 2.b http://www.merriam-webster.com/dictionary/tilde).
Replace the BOM with a magic coding comment.  Issue #131
Hide magic comment when printing RubyGems release notes
`gem cleanup` continues cleaning up gems if one can't be uninstalled due to permissions.  Issue #82
Fix uninstallation of --user-installed gems
- Gem repository directories are no longer world-writable.  Patch by Sakuro OZAWA.  Ruby Bug #4930
Hide non-rubygems-owned bugfix monkey patches from RDoc
Moved 'Pushing gem' message to the push command
Fixed tests I broke by ignoring terminate_interaction from gemcutter_utilities
Seriously... gemcutter_utilities shouldn't ever exit
- The encoding of a gem's YAML spec is now UTF-8.  Issue #149
+ fetch_command should pass in Dir.pwd for the download location.
+ RemoteFetcher should allow for Dir.pwd and leave it alone (no cache).
fake fetcher should follow suit.
+ RemoteFetcher#download now raises ArgumentError on bad scheme.
minor cleanup