prevent all new gems to be rubygems 2.0 only
Use the form of OSI's official site

See http://opensource.org/licenses/MIT.
Add warning message when Gemfiles use source with a block.
Performance: memoize expanded path of Source::Path
Performance: pre-calculate expensive `prerelease?` values during resolve
Merge pull request #3204 from dubek/setup-performance-improvements

Setup performance improvements
Merge pull request #3199 from danfinnie/stable-1-6-source-warning

Add warning message when Gemfiles use source with a block.
Fix a typo in the docs.
Document config for HTTPs source credentials
Fix a typo in the docs.
Reword credential docs for consistency and spelling
Merge pull request #3116 from grosser/grosser/metadata

prevent all new gems to be rubygems 2.0 only
Merge pull request #3168 from yous/patch-license

Use LICENSE.txt with the form of OSI's official site
Version 1.6.7 with changelog
Merge tag 'v1.6.7'

Conflicts:
	CHANGELOG.md
	lib/bundler/dsl.rb
	lib/bundler/version.rb
Performance: lazily memoize expensive `prerelease?` values during resolve