Add specs around GradientGeneratorCtrl
Add tests to colors service

* Refactor rgb to hex function
Add specs around SwatchFactory
Add specs around ColorPicker directive
Add specs around Slider directive
Add specs around GradientPreview directive
Add specs around GradientCode directive
Add some basic tests to jquery plugin directives
Add specs around Swatch class
Add specs around GradientGenerator class
Add unprefixed gradient to sample
Get middleman_jasmine:ci working
Set up CircleCi