Core: use shlex splitting instead of whitespace splitting for client …

…and server commands

MultiServer.py

@@ -15,6 +15,7 @@
 import operator
 import pickle
 import random
+import shlex
 import threading
 import time
 import typing
@@ -1150,7 +1151,7 @@ def __call__(self, raw: str) -> typing.Optional[bool]:
         if not raw:
             return
         try:
-            command = raw.split()
+            command = shlex.split(raw, comments=False)
             basecommand = command[0]
             if basecommand[0] == self.marker:
                 method = self.commands.get(basecommand[1:].lower(), None)