add coveralls
fix coveralls build errors for other Gemfiles
rails 4 requires ruby 1.9.3+, so do not test
move coveralls to rails 4 Gemfile, only run once (with latest ruby)
Remove minitest. It is defined as a development dependency in the gemspec.
mmircea16 Addressing issue 694: Moved the logic determining the captured text into helpers.rb:
  - Added test to replicate issue
  - Added simple test to expand coverage
  - Moved code determining the kind of output from action_view_mods - capture_with_haml to helpers - capture_haml
mmircea16 Refactoring: Extracted logic that prettifies a text into a method
mmircea16 Refactoring: Collapsed an intricate if in capture haml to a simpler one
mmircea16 Refactoring: Inlining the template content for test_render_method_returning_null_with_ugly and removing the template file used before
mmircea Refactoring: Making the prettify method private