indention fixes in buildbot.clients package
Added method to disconnect TextClients from master.

Added TextClient.disconnect() method, to cleanly closing connection
to build master.
terminate 'buildbot statusgui' command when it's window is closed

When statusgui window is closed, disconnect from master. Disconnecting
from master will stop the reactor and terminate the command. Previously
the reactor was left running and command did not exit properly when
window was closed.
fixed termination of 'buildbot debugclient' when connected to master

When debugclient window is closed, disconnect from master and stop the
reactor, this will terminate the command. Previously if debugclient was in
connected state, it did not quit properly.