Multiworld core implementation By Bonta0

Does not include the server/client code or the rom writes
specific to it. Indeed it cannot write multiworld roms at
all right now, pending addition future updates to support
the official ALTTPR Multiworld client.

Includes some GUI changes by Alaszun

Co-authored-by: Alaszun <koelze@google.com>

EntranceRandomizer.py

@@ -8,7 +8,7 @@ import sys
 
 from Gui import guiMain
 from Main import main
-from Utils import is_bundled, close_console
+from Utils import is_bundled, close_console, output_path
 
 
 class ArgumentDefaultsHelpFormatter(argparse.RawTextHelpFormatter):
@@ -213,8 +213,15 @@ def start():
                             Output .json patch to stdout instead of a patched rom. Used
                             for VT site integration, do not use otherwise.
                             ''')
+    parser.add_argument('--multi', default=1, type=lambda value: min(max(int(value), 1), 255))
+    parser.add_argument('--skip_playthrough', action='store_true', default=False)
+
+    parser.add_argument('--outputpath')
     args = parser.parse_args()
 
+    if args.outputpath and os.path.isdir(args.outputpath):
+        output_path.cached_path = args.outputpath
+
     if is_bundled() and len(sys.argv) == 1:
         # for the bundled builds, if we have no arguments, the user
         # probably wants the gui. Users of the bundled build who want the command line