Fix issue with assistant editors and sequential delete commands.
(codeEditor could change to an assistant that was not in focus, and subsequent deletes would happen there)
uncommented funtionality to set the cursor to the line following the deleted line.
Only update ivars when a command happens.
Couldn't determine a reason to update the ivars on every selection change, when we can just calculate them when needed. Should save a lot of calculation as user types.
When duplicating a line, put the cursor at the end of the existing line, instead of the beginning.
When deleting a line, put the cursor at the end of the following line, instead of the beginning.
Merge pull request #6 from pwxn/master

Fix issue with assistant editors and sequential delete commands.