Added a powerful console to FlxDebugger

Initial commit for a recreation of Eric Smith's  "CoolConsole" in haxe,
integrated into the flixel debugging screen and preloaded with a set of
already installed commands. It is possible to easily add your own
commands via FlxG.addCommand.
Fixes and new features

- Now compiles and works on cpp targets
- Added command shortcuts
- FlxG.addCommand now works propertly with FLX_NO_DEBUG
- The game auto-pauses when the console has focus now
- You can now use escape to un-focus the console
- The cursor won't jump to index 0 of the textfield anymore when
browsing through the command history
- watchMouse and create commands fixed (use system cursor pos)
- set command now works properly
Override the default debugger layout for now
Console: debuggerLayout support and more

- added support for all the debugger layouts
- garbage collection
- added tempDisablesSoundHotKeys var to avoid overriding the devs
preferences regarding the sound tray
Central FlxSave for cmdHistory and sound prefs

- added prefsSave FlxSave to FlxG to save the console's command history
and the sound prefs in one place
- added pause command
- solved conflict with "cl" alt command
- moved addCommand logic entirely into FlxG
- fix for the height of watchEntries being a bit to small to fully be
shown
Temp fix for buggy commit
Introducing registration, new call command

- Introduced registration of objects for the set command and functions
for the new call command
- removed addCommand from FlxG and added a reference to the console
- removed pauseSounds, resumeSounds and volume commands
- added listObjects, listFunctions, call
- substantial change of the help command, now provides info on
individual commands
- added autoPause variable to the console
- improved error prevention
- cleaned up Console.hx a bit
Fix bug with _prefsSave
Rename Commands to ConsoleCommands
Merge pull request #346 from Gama11/dev

Add console to debugging screen