Added the ability to get more information on the SBThread's stop reason

by being able to get the data count and data. Each thread stop reason
has one or more data words that can help describe the stop. To do this
I added:

    size_t
	SBThread::GetStopReasonDataCount();

	uint64_t
	SBThread::GetStopReasonDataAtIndex(uint32_t idx);

llvm-svn: 119720