scripted-diff: Rename mininode to p2p

-BEGIN VERIFY SCRIPT-
sed -i 's/\.mininode/\.p2p/g' $(git grep -l "mininode")
git mv test/functional/test_framework/mininode.py test/functional/test_framework/p2p.py
-END VERIFY SCRIPT-

test/functional/p2p_sendheaders.py

@@ -87,7 +87,7 @@ e. Announce one more that doesn't connect.
 """
 from test_framework.blocktools import create_block, create_coinbase
 from test_framework.messages import CInv
-from test_framework.mininode import (
+from test_framework.p2p import (
     CBlockHeader,
     NODE_WITNESS,
     P2PInterface,