Patch enabling lldb command line driver to run on windows.

CHANGES:
- Thread locking switched from pthreads to C++11 standard library.
- Abstracted platform specific header includes into 'platform.h'.
- Create editline emulator for windows.
- Emulated various platform dependant functions on windows.
TODO:
- User input currently handled by gets_s(), work started on better handler:
    see _WIP_INPUT_METHOD define blocks in 'ELWrapper.cpp'.
    Aim is to handle 'tab' auto completion on windows.
- Tidy up 'getopt.inc' from lldbHostCommon to serve as LLDB Drivers getopt windows implementation.

llvm-svn: 192714