Update name in LICENSE
Change indentation level to 4 spaces
Nit: Fix statement exceeding 100-character line limit
Follow AOSP style guide
Add visibility modifiers
Create and use Direction enum instead of constants
Move all Beam subclasses to a single file
Rewrite invalid beam direction error message
Fix crash when creating new touch beams
Follow AOSP style guide in naming constants
Rename opacity to alpha
Write and use nextInt() convenience method
Refactor Beam hierarchy and API