Add working --help option to deploy environment and deploy display
running r10k deploy environment --help previously attempted to deploy rather than showing help
consequently, there was no documentation internally for the commonly-used -p option
(GH-90) Prevent name collisions with multiple sources

Previously, when environments were being interacted with, a lookup table
was being created of names and associated environments for determining
what environments should be acted upon. However this didn't take into
account multiple sources where multiple environments could coexist with
the same name. In this case the duplicate environments would be silently
ignored.

This is resolved by getting rid of the lookup table and just scanning a
list of environments with the given names. It's a bit slower can could
theoretically take a fair amount of time, but that would require a
situation with 1k+ environments. For most normal operations
this will be very fast, and won't have the same collision issues.
Merge branch 'bugfix/1.1.x/gh-90-environment-name-collision' into 1.1.x
Update CHANGELOG and version for 1.1.4
Switch to help command approach
Depends on pull request #25 on ddfreyne/cri to allow subcommands to have help run on them
Merge branch '1.1.x'

Conflicts:
	CHANGELOG
	lib/r10k/task/deployment.rb
	lib/r10k/version.rb
break up how refs get resolved
Stub out remote head
[git/repository] Expose remotes info
[git/repository] Control whether git commands raise on fail
[git] Allow repos to resolve remote refs
[util/subprocess/result] add #failed? and #succeded?
[git] Refactor resolve_* methods to return nil instead of raise

The code invoking the resolve methods had to call/rescue everything
instead of checking for nil. This commit refactors that code to indicate
failure by returning nil and let callers determine if an exception
should be raised.
[git/working_dir] deduplicate working dir update code
[git/working_dir] Fetch cache refs before checking out
Merge branch 'bugfix/master/track-remote-ref'
Update CHANGELOG and version for 1.2.0rc2
(maint) Fixup specs for 1.8.7
Update CHANGELOG for 1.2.0
Remove excess whitespace