patch_match_stereo can now use a custom config using the --config_path option instead of just relying on the default patch-match.cfg from the workspace. Also a new option for patch-match is introduced (--PatchMatchStereo.allow_missing_files) to allow the process to ignore missing source images or depth/normal maps and simply exclude that image index from the patch-match problem without error.

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Co-authored-by: Antonios Matakos <anmatako@dss.microsoft.us>