Refactoring.

Removed XML comments for private and internal members.
Improved XML comments.
Made a number of members and internal.
Implemented a Container abstractation.
Renamed HotkeyCombination to Hotkey.
Removed underscore prefix from field names.
Line-broke comments to stay within 80 chars width.
Tweaked comment.
HotkeyContainer now uses composition instead of inheritance.
Marked the members of the Forms namespace as internal.
Resolved merge conflict.