[QA] restructure rpc tests directory

* move non-test classes to subdir `test-framework`

qa/rpc-tests/getblocktemplate_proposals.py

@@ -3,9 +3,8 @@
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
-from test_framework import BitcoinTestFramework
-from bitcoinrpc.authproxy import AuthServiceProxy, JSONRPCException
-from util import *
+from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import *
 
 from binascii import a2b_hex, b2a_hex
 from hashlib import sha256