Lock objects- Walls, Area, Racks

[justin-davisibm]

This feature partially closes #6, by providing a mechanism to lock/unlock Areas within the canvas.

To process this change: I've added an additional custom_meta.object_type field to the wall and area objects, mirroring what you already use for the overall floor area and racks.

A new Lock/Unlock Object button is added to the left hand nav, acting as a toggle switch- calling lock_floorplan_object()

The lock_floorplan_object() function evaluates the selected object, determines if it is a wall, area or other (based on code the "other" option would be rack. When the object is locked, rotation, X/Y movement and the mt, mb, ml, mr and mtr resize/rotation props are disabled.

When the object is unlocked:

• If it is a Rack: Rotation, X/Y movement and mtr rotation props are re-enabled
• if it is a Wall/Area: rotation, X/Y movement and the mt, mb, ml, mr and mtr resize/rotation props are re-enabled.

I do believe this is a semi-breaking change for existing wall/area uses. If desired I could likely add in an edit/redraw section to the toggle to handle an undefined case. Let me know.