[build] Update build files to latest Gradle
[library] Fix javadocs errors in TwoWayView
[library] Replace compareTo() calls with simple comparisons
[library] Remove unnecessary semicolon in TwoWayView
[library] Supress 'unused' warning on TwoWayView's public API
[library] Simplify a few conditional statements
[library] Simplify forceLayout() loop on scrap views
[library] Use measured width in measureWidthOfChildren()

Fixes #60