Deletes the locally stored node

@BrettASwift 

This is an incomplete PR, can you add the call to delete tab from the blockly UI?  Or just send me a message on how to do that?



`var blocklyTop = document.getElementByID( "blocklyWrapper-top" );`
`var tab = document.getElementByID( nodeID );`
`blocklyTop.removeChild( tab );`

Something like that should do it.