Prevent making useless symbols.

Groups are concatenated with ':' in Bundler::Settings#without=,
and splited by ':' in Bundler::Settings#without. So replace ' '
with ':' to prevent making useless symbols and other objects.
Show that current_release can be overridden.
Sort `bundle outdated` output (as `bundle show`) ; add tests.
Ruby 1.8.7 does not have lookbehind ; fix the regex.
Adds bundle licenses cli task
Add :gist option for gems embedded in gists
Allow optional gem push via gem_push environment variable.
Issue #2000 Add test for conflict markers in Gemfile.lock
Raise error if Gemfile.lock contains conflict markers, closes #2000
Issue #2000 improve error message
Issue #2000 Improve test for conflict markers in lockfile
Merge remote-tracking branch 'upstream/master' into issue-2000
change to new expect syntax for rspec
backport API timeout spec fixes
Remove trailing whitespace
Merge pull request #2169 from sol/1-2-stable

Remove trailing whitespace
backport @tenderlove's fix for Psych::SyntaxError

only parse specs as YAML if they look like YAML files, otherwise fall back to Ruby evaluation

Fixes #2188
backport smarter psyched yaml
Version 1.2.3 with changelog
remove sources of two outstanding warnings