Callback params for FlxButton, remove broken "on"-variable
Several improvements for DebuggerFrontEnd
Merge pull request #479 from Gama11/dev_DebuggerFrontEnd

Several improvements for DebuggerFrontEnd
Prevent FlxButton params from becoming null
Merge pull request #478 from Gama11/dev_FlxButton

Callback params for FlxButton, remove broken "on"-variable, closes #432