UI Improvement + Layout Management

[brianuuu]

UI Improvements

• Added searching function to Object Palette
• Object Properties, transform and help box are now moved to right side where all object related information is located
• A dedicated list for layouts is added
• Added "Move selected objects to layer..." option to Edit menu
• Selecting multiple objects now also show layer name if they share the same one

Layout Management

• Allow changing layer visibility quickly
• Double clicking a layer selects all objects in that layer
• Select a layer and click again allows renaming
• Working layer specify where new objects will be placed

Bug Fixes

• Fixed closing glvl without saving doesn't undo file rename/removal, now force always unpack ar when loading a level
• Remove all test objects placed when loading a level
• Fixed when adding/cloning objects, object property menu did not clean up, so when you cancel new object placement the property of previous object is still being displayed
• Fixed switching terrain mode not cleaning up object property window
• Fixed manually changing transform does not have undo/redo
• Make spin control for transform actually work
• Fixed selecting different MultiSetParamObject doesn't update object name
• Fixed when clicking Undo/Redo on menu bar doesn't update axis model, unlike pressing Ctrl+Z/Y
• Allow Ctrl select object to deselect objects