[merge] Control-backspace to drop into the debugger

[John Arbash Meinel]

John Arbash Meinel has voted +1 (conditional).
Status is now: Semi-approved
Comment:
It should have a disable flag

and it needs some PEP8 cleanups.

Otherwise +1

For details, see: 
http://bundlebuggy.aaronbentley.com/request/%3Ce01316480704162359m6128bc83vc823d9ca73d7ca8f%40mail.gmail.com%3E