First attempt at automated out-of-process crash reporting. Have only
updated AppVeyor script so far, so if this works (which it won't), it'll
only work on Windows.
Minor CMake improvement that becomes a major improvement on Windows,
because for some reason OpenEXR on Windows always crashes if you mix
release/debug builds (e.g. release OpenEXR + debug Olive and vice versa).
This ensures that as long as you have both release and debug (which you
will if you installed from vcpkg), CMake will link the correct lib and
prevent crashes.
This likely isn't necessary, but was one of the steps made trying to debug
MSVC compilation. Considering the previous iteration was from 2012 and this
one is from 2019, it may have other improvements.