Windows build fixes and removal of endlessly recursive termination function.

This change removes the ScriptInterpreter::TerminateInterpreter() call which
ended up endlessly calling itself as things currently stand.  It also cleans
up some other Windows-related cmake changes.

See http://lists.cs.uiuc.edu/pipermail/lldb-commits/Week-of-Mon-20140630/011544.html
for more details.

Change by Zachary Turner