Last refactor, introducing ButterKnife and all those things, I forgot to
update this layouts.

Removed the sign up dialog, log in one is enough with the third button I
added some time ago to sign up.

Removed classes we don't need due to the libraries I have recently
introduced.

Initial status message is "not connected", rather than "unknown".

This return to "app" instead of "bitmask_android" is due to this reading: https://developer.android.com/sdk/installing/studio-build.html#projectStructure
I'll have to tweak the final apk name in build.gradle.

This way, gradle commands generate apks correctly named.