* Added Attributes namespace to hold custom attributes.
* UnusableAttribute.cs - Added to tag classes as unusable by the editors regardless if they inherit from BaseObject or not.
* BaseObject.cs - Contains OnEnter and OnExit methods
* InitialLocation.cs - UnusableAttribute tag applied.
Room Designer:
* frmMain.cs - Additional Script UI design.
* frmMain.cs - Added plugin support.
Plugin support is being tested. Room Designer is the testbed. It will ultimately end up inside MUDEngine.Engine. Curently (if ROOT/Plugins exists) loads all .dll files contained within the plugin directory. All classes inheriting from BaseObject and not tagged with the UnusableAttribute attribute automatically get added to the script editor.
