Remove NMakefile. CMake is now the build system for Windows

Change-Id: I5ccf0369a3cfaa57feada3261ce2abe03a6b7aa0
Reviewed-on: http://review.couchbase.org/33311
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>