Relocate gem_dependencies to helpers block
Filter gems with nil specs out of the dependency report -- fixes crash
Fix support for platform dependent gems

A gem can be uploaded for different platforms, and all of them are
stored and can be deleted and downloaded.
Merge pull request #97 from edmundoa/multi-platform

Fix support for platform dependent gems
Merge pull request #95 from whitepages/fix_missing_spec_crash

Fix crash when gemspec is missing for a named gem
Support nil `gems` param on dependencies call
Merge pull request #108 from soffes/master

Fix 500 when the `gems` parameter is excluded from the dependencies call
Test the blank API request bundler now makes.
Fix bundler deprecation warning.
Add support for overwriting existing Gem.

Added command line -o or --overwrite.  Tested with Ruby-1.9.3-p392.  Updated
readme.markdown with new options.  Revised version.  Current gems require
Gemfile to source rubygems.org via HTTPS.
Don't override by default.

Default to server configured behavior when override not set. Previously,
override unaware clients would always override.
Fix compatibility with rubygems 2.0.x
.gem/credentials needs correct permissions.