Fix asset interdependencies with bower

[toadkicker]

I propose we implement using bower for managing the internal dependencies of the asset pipeline.

• configure bower.json
• remove static and less sources
• remove less-rails and therubyracer
• create constant value for bower_components folder path
• locate paths pointing to static and less files
• refactor static install generator to compile sources and copy assets into host rails app's assets/bower_components. probably requires gsub on initializers/assets.rb
• write test that spins up a mock rails app and checks for 404's

[toadkicker]

Other advantages:

We can get rid of dependencies on therubyracer, less-rails
Will improve test code coverage
Simplify the static install method
Reduce complexity in the gem