More work on international keyboards.

Changed the English US keymaps to implement a strict US key map
with no additional ALT functions.

Fixed a bug copying the alias in the InputDevice copy constructor.

Added support for end of line comments in KCM and KL files.

Added the German keyboard layout.

Sorted the keys in the keyboard layout files by physical arrangement
to make it easier to maintain them.

Bug: 6110399
Change-Id: If44d83de5b98f2bf0016cbb8e12264387b286aaa