SERVER-9771 allow libdeps to process emitter intermediate output with targets that may be strings
SERVER-9771 build Windows dynamic library C++ driver

Add generate_def.py script for windows dll.
Expose all public symbols found in the static library.
Note that the static Windows library may not work properly, as
not all obj modules may be included by the linker, despite their
necessity for their global initializers.  This dynamic library
will include all necessary obj modules.