This updates all code to make use of the new chainhash package since the
old wire.ShaHash type and related functions have been removed in favor
of the abstracted package.
Also, while here, rename all variables that included sha in their name
to include hash instead.
Finally, update glide.lock to use the required version of btcd, btcutil,
and btcrpcclient.
This commit corrects various things found by the static checkers
(comments, unkeyed fields, return after some if/else).
Add generated files and legacy files to the whitelist to be ignored.
Catch .travis.yml up with btcd so goclean can be run.
