Branch/blockly button

Juan's suggestion was that in third person if you click on the rover that the 3D blockly button becomes visible(and then you would have to click on the 3d blockly button to make the blockly UI visible).  The code is hiding the button correctly, but the inventory is changing the visibility when the camera switches to third person.  I'd suggest we move the inventory down one level so that the button doesn't have it's visibility changed.  

This pull request goes along with the branch/blockly-button from vwf.