Add support for ANSI codes

Closes https://github.com/CocoaPods/CLAide/issues/17
[Command] Use only TTY check for ANSI output

CLAide includes by default the stub string mixin to prevent crashes (CLAide was
using the blue method but not checking for it). The additional initialization
time should be negligible and offset by the removal of conditional logic.

The specs are forced to run with ANSI disabled to prevent inconsistency issues.
Add kicker configuration
[Specs] Fix coverage
[Rake] Clean up
[Rubocop] Setup
[Mixins] Add String#strip_margin
[Specs] Cleanup heredoc indentation
[ZSHCompletionGenerator] Cleanup heredoc indentation
[Rubocop] Add TODO configuration
[Rubocop] Fix ColonMethodCall
[Rubocop] Fix EmptyLines
[Rubocop] Fix EmptyLinesAroundBody
[Rubocop] Fix IndentationWidth
[Rubocop] Fix LeadingCommentSpace
[Rubocop] Fix NegatedIf
[Rubocop] Fix NilComparison
[Rubocop] Fix PercentLiteralDelimiters
[Rubocop] Fix RedundantSelf
[Rubocop] Fix SingleSpaceBeforeFirstArg