Added --relative-only option to bat pack command

This makes BAT skip assets that are referred to with an absolute path.
It is assumed that the receiver of the BAT pack can access those assets
at the same path.

blender_asset_tracer/cli/pack.py

@@ -58,6 +58,9 @@ def add_parser(subparsers):
                              'packing into a directory (contrary to ZIP file or S3 upload). '
                              'Note that files will NOT be compressed when the destination file '
                              'already exists and has the same size as the original file.')
+    parser.add_argument('-r', '--relative-only', default=False, action='store_true',
+                        help='Only pack assets that are referred to with a relative path (e.g. '
+                             'starting with `//`.')
 
 
 def cli_pack(args):
@@ -82,6 +85,9 @@ def create_packer(args, bpath: pathlib.Path, ppath: pathlib.Path,
         if args.compress:
             raise ValueError('S3 uploader does not support on-the-fly compression')
 
+        if args.relative_only:
+            raise ValueError('S3 uploader does not support the --relative-only option')
+
         packer = create_s3packer(bpath, ppath, tpath)
     elif tpath.suffix.lower() == '.zip':
         from blender_asset_tracer.pack import zipped
@@ -89,9 +95,11 @@ def create_packer(args, bpath: pathlib.Path, ppath: pathlib.Path,
         if args.compress:
             raise ValueError('ZIP packer does not support on-the-fly compression')
 
-        packer = zipped.ZipPacker(bpath, ppath, tpath, noop=args.noop)
+        packer = zipped.ZipPacker(bpath, ppath, tpath, noop=args.noop,
+                                  relative_only=args.relative_only)
     else:
-        packer = pack.Packer(bpath, ppath, tpath, noop=args.noop, compress=args.compress)
+        packer = pack.Packer(bpath, ppath, tpath, noop=args.noop, compress=args.compress,
+                             relative_only=args.relative_only)
 
     if args.exclude:
         # args.exclude is a list, due to nargs='*', so we have to split and flatten.