Problem: Get warning for deleting autocommand group when the autocommand
using the group is scheduled for deletion. (Pavol Juhas)
Solution: Check for deleted autocommand.
Problem: Deleting an augroup that still has autocmds does not give a
warning. The next defined augroup takes its place.
Solution: Give a warning and prevent the index being used for another group
name.
Problem: Crash when using tabnext in BufUnload autocmd. (Norio Takagi)
Solution: First check that the current buffer is the right one. (Hirohito
Higashi)
Problem: The BufUnload event is triggered twice, when :bunload is used with
set to or .
Solution: Do not trigger the event when ml_mfp is NULL. (Hirohito Higashi)
Problem: When using feedkeys() in a timer the inserted characters are not
used right away.
Solution: Break the wait loop when characters have been added to typebuf.
use this for testing CursorHoldI.