Lots of improvements from the dev branch.

* Fix backdrop removal bug when backdrop is off
* Prevent click propagation from select component
* Fixes hide dropdown once and for all -- uses send instead of calling hideDropdown
* Selected color picker cell shows transparent indicator
* Allow disabling select component
* Color picker: handle rgba and transparent color
* Color picker: bug fix
* Color picker: tests
* Update popover titles
* Update popover examples and spacing in popover titles
* Fix app.less
* Update karma packages so that npm install works
* ESC key closes modals, configurable with the escToCancel flag.
* Use Underscore.js _.bind() instead of Function.prototype.bind()
* Remove addepar style guide dependency
* Use bootstap 3.1.1 instead of addepar-bootstrap
* Separate bower and non-bower deps
* Add minified ember-widgets file
* Rename bower-managed folder "lib" -> "vendor"
* Add missing images to src/img
* Listen to the correct element in Carousel.
* Update README and add CONTRIBUTING.md