"Dangerous" hotkey in server status dialog

[Magnus Hagander <magnus(at)hagander(dot)net>]

If you select a row in the server status dialog and hit escape, pgadmin
will ask to cancel the query.

On every platform I've worked on, escape means close the dialog, not
actually do something.

I think this is becuase we are using wxID_CANCEL, which is the default
mapping there. I think the proper solution is to invent our own id
instead. Same for the one under locks. I can't see any reason why we're
overloading this with the default behaviours.

I'd go as far as calling this a bug and say we should probably backpatch
a fix ;-)

Comments?

//Magnus