This commit fixes the module-level docstrings for the tests and helper
modules in qa. Many of these tests were uncommented previously - this
commit ensures that every test case has at least a minimum level of
commenting.
bip65-cltv.py is based on the earlier BIP66 soft-fork RPC test
implemented by Pieter Wuille's 819bcf9b99
bip65-cltv-p2p.py is based on the earlier BIP66 P2P test by Suhas
Daftuar's d76412b068
