use guard-compat
add rspec to Gemfile
Convert specs to RSpec 3.1.7 syntax with Transpec

This conversion is done by Transpec 2.3.8 with the following command:
    transpec

* 1 conversion
    from: stub('something')
      to: double('something')

For more details: https://github.com/yujinakayama/transpec#supported-conversions
update to Rspec 3
update specs to RSpec
replace mocha with rspec so Travis works
Merge pull request #119 from guard/use_guard_compat

Use guard compat