Split signrawtransaction into wallet and non-wallet

Splits signrwatransaction into a wallet version (signrawtransactionwithwallet) and
non-wallet version (signrawtransactionwithkey). signrawtransaction is marked as DEPRECATED
and will call the right signrawtransaction* command as per the parameters in order to
maintain compatibility.

Updated signrawtransactions test to use new RPCs

test/functional/test_framework/util.py

@@ -472,7 +472,7 @@ def random_transaction(nodes, amount, min_fee, fee_increment, fee_variants):
     outputs[to_node.getnewaddress()] = float(amount)
 
     rawtx = from_node.createrawtransaction(inputs, outputs)
-    signresult = from_node.signrawtransaction(rawtx)
+    signresult = from_node.signrawtransactionwithwallet(rawtx)
     txid = from_node.sendrawtransaction(signresult["hex"], True)
 
     return (txid, signresult["hex"], fee)
@@ -552,7 +552,7 @@ def create_lots_of_big_transactions(node, txouts, utxos, num, fee):
         newtx = rawtx[0:92]
         newtx = newtx + txouts
         newtx = newtx + rawtx[94:]
-        signresult = node.signrawtransaction(newtx, None, None, "NONE")
+        signresult = node.signrawtransactionwithwallet(newtx, None, "NONE")
         txid = node.sendrawtransaction(signresult["hex"], True)
         txids.append(txid)
     return txids