[PATCH] Add glretrace option '--snapshot-format=MD5' that allow write image MD5 to a text format file.

[Alexander Monakov]

Let's hear what more experienced (than myself) maintainers say.

Regarding the patch itself, it should avoid adding irrelevant files in
thirdparty (such as VS project files), and references to libcrypto should be
removed from CMakeLists.txt.

Alexander