Debugger shorcuts preferences

[Vladimir Prus]

Hello!

At the moment, the debugger does not have any shortcuts at all, which makes
it rather inconvenient to use. I'm planning to add shortcuts, but what they
should be? My preference is:

F9 -- Continue
F10 -- Step over
F11 -- Step into
F12 -- Step out

So all debugger shortcuts are on the same block of F-keys.

Any better suggestions or comments?

- Volodya