Fixed bug #963: Xdebug waits too long for response from remote client

Instead of relying on the OS socket connect timeout, we now put the socket into
non-blocking mode and use select() to simulate a socket connection time-out.
The time-out is configured to be 200ms and can at the moment not be changed.
Merged pull request #90
Merge branch 'xdebug_2_2'
Merge branch 'master' of github.com:xdebug/xdebug