message: Fixed inconsistencies between code and comments
  1) Makes the code for block 44 consistent with  the expected figure in
  the comment above it by adding a transaction to the block
  2) Fixed comment describing sign_tx() function
diff: @@ -591,6 +591,8 @@ class FullBlockTest(BitcoinTestFramework):
  b44.hashPrevBlock = self.tip.sha256
  b44.nBits = 0x207fffff
  b44.vtx.append(coinbase)
  + tx = self.create_and_sign_transaction(out[14], 1)
  + b44.vtx.append(tx)
  b44.hashMerkleRoot = b44.calc_merkle_root()
  b44.solve()
  self.tip = b44
  @@ -678,7 +680,7 @@ class FullBlockTest(BitcoinTestFramework):
  # Test block timestamps
  # -> b31 (8) -> b33 (9) -> b35 (10) -> b39 (11) -> b42 (12) -> b43 (13) -> b53 (14) -> b55 (15)
  # \-> b54 (15)
  - #
  + # -> b44 (14)\-> b48 ()
  self.move_tip(43)
  b53 = self.next_block(53, spend=out[14])
  self.send_blocks([b53], False)
  @@ -1308,7 +1310,7 @@ class FullBlockTest(BitcoinTestFramework):
  return create_tx_with_script(spend_tx, n, amount=value, script_pub_key=script)
  # sign a transaction, using the key we know about
  - # this signs input 0 in tx, which is assumed to be spending output n in spend_tx
  + # this signs input 0 in tx, which is assumed to be spending output 0 in spend_tx
  def sign_tx(self, tx, spend_tx):
  scriptPubKey = bytearray(spend_tx.vout[0].scriptPubKey)
  if (scriptPubKey[0] == OP_TRUE): # an anyone-can-spend
  