Blender Git Loki

Windows: Support backtraces on release builds.

This diff add supports for crash logs on windows for
release builds. This can be toggled on/off with the
`WITH_WINDOWS_PDB` cmake option. by default it is on.

Things to take into consideration:

Release builds are hightly optimized and the resulting
backtraces can be wrong/misleading, take the backtrace
as a general area where the problem resides rather than
an exact location.

By default we ship a minimized symbol file that can only
resolve the function names. This was chosen to strike
a balance between growth in size of the download vs
functionality gained. If more detailed information is
required such as source file + line number information
a full pdb can be shipped by setting `WITH_WINDOWS_STRIPPED_PDB`
to off.

Differential Revision: https://developer.blender.org/D7520

Reviewed by: brecht