Delete files that shouldn't be versioned.

- Removed IDE bing and gen folders.
- Removed IntelliJ IML files.
- Etc.
Moved sdk versions to build.grade

Moved properties like the compile SDK version, build tools version,
mind SDK version, etc to the build.gradle file that way it can be
imported into any Android Studio project without the need for the
parent gradle.properties file.
Addressed a show/hide animation bug.

The original code base contained a bug where if the user quickly swiped
up and down repeatedly on the AbsListView that a FAB was listening to,
the FAB would lose track of it’s original Y position and would slowly
scroll off screen never to be seen again. This fix has the FAB make a
note of it’s displayed Y position after it is assigned in onLayout()
and use it when animating instead of it’s current Y position.