deprecate stats middleware

Change-Id: Iba60958e18c2ccc41706c83d20b80a0bf1b13ad4
Implements: bp deprecated-as-of-icehouse
Make boolean query filter "False" argument work

Currently passing parameter=False returns the results
for parameter=True, so make the boolean evaluation of
the query string parameter more robust by using
oslo strutils.bool_from_string

Change-Id: I189a4f4a2e6448698903b949bdf74d5ef25d338b
Closes-Bug: #1267530
Merge "Make boolean query filter "False" argument work"
Merge "deprecate stats middleware"