Attempt to make kgdb little more useful and easy to use. Properly initialize

Attempt to make kgdb little more useful and easy to use.  Properly initialize
it to recognise what ABI  to use on amd64 (and possibly others) platform.
Display PID and process name as a part of the 'info threads' output, TIDs
alone are too confusing. Introduce new commmands 'tid <tid>' and 'proc <pid>'
to accompany gdb's default 'thread <thread num>' to make the task of switching
between different contexts easier.