Dagger 2 improvements

[rogerhu]

• Producers (http://frogermcs.github.io/dependency-injection-with-dagger-2-producers/)
• Subcomponents
  • https://medium.com/@methodsignature/dagger-2-dependency-injection-for-android-developers-51d60e7397e6#.5vp5hj5hg)
  • https://medium.com/azimolabs/dagger-2-on-production-reducing-methods-count-5a13ff671e30#.vmy4x6r6f
• Calling out the use of runtime parameters
• Testing Dagger 2 modules (http://google.github.io/dagger/testing.html)
• http://www.slideshare.net/nakhimovich/advanced-dagger-talk-from-360anDev