Fix compilation on Mac OS which lacks _strupr, _strlwr, and _unlink
Merge pull request #1 from noa--/gridfs_macos

Fix compilation on Mac OS which lacks _strupr, _strlwr, and _unlink
Refactored code to allow it to compile on MacOS
Merge remote-tracking branch 'refs/remotes/Mongo/master' into mongo-master-pull-request-gridfs
Merge branch 'refs/heads/mongo-master-pull-request-gridfs' into development

Conflicts:
	src/gridfs.c
	src/gridfs.h
	src/mongo.c
	test/gridfs_test.c
Removed some warnings on mongo.c and warning due to repeated _CRT_SECURE_NO_WARNINGS when this is defined on Visual Studio compiler as a default define
Merge remote-tracking branch 'refs/remotes/Mongo/master' into mongo-master-pull-request-gridfs
Merge pull request #106 from jsbattig/mongo-master-pull-request-gridfs

Mongo master pull request gridfs