* remote.c (remote_get_threadinfo) : Support for remote
multithread debugging.
(remote_get_threadlist) : get a partial list of threads
(remote_threadlist_iterator) : Step through all the threads
(init_remote_threadtests) : Optional builtin unit test commands.
* thread.c (bind_target_thread_vector) : Implementa a more dynamic
way of accessing target specific thread info functions than
FIND_NEW_THREADS.
(target_thread_info) : Function to get extended thread information.
* gdbthread.h : Export internal data structures corresponding to
external detailed thread info response. This is more like a 'ps'
command than what might be expected of host based threads. This
is for embedded systems.