Namecoin / AuxPoW: Bump frame size limit to 20 MB

Fixes #27

electrum/interface.py

@@ -53,6 +53,12 @@ def __init__(self, *args, **kwargs):
         self.in_flight_requests_semaphore = asyncio.Semaphore(100)
         # disable bandwidth limiting (used by superclass):
         self.bw_limit = 0
+        # The default Bitcoin frame size limit of 1 MB doesn't work for
+        # AuxPoW-based chains, because those chains' block headers have extra
+        # AuxPoW data.  A limit of 10 MB works fine for Namecoin as of block
+        # height 418744 (5 MB fails after height 155232); we set a limit of
+        # 20 MB so that we have extra wiggle room.
+        self.framer.max_size = 20000000
 
     async def handle_request(self, request):
         # note: if server sends malformed request and we raise, the superclass