Add a "thread specification" class that specifies thread specific breakpoints by name, index, queue or TID.  
Push this through all the breakpoint management code.  Allow this to be set when the breakpoint is created.
Fix the Process classes so that a breakpoint hit that is not for a particular thread is not reported as a 
breakpoint hit event for that thread.
Added a "breakpoint configure" command to allow you to reset any of the thread 
specific options (or the ignore count.)

llvm-svn: 106078