Sync db, db.sqlalchemy from oslo-incubator 0a3436f

This change sync's oslo-incubator's db module from commit hash
0a3436fbcd69b7e0cd1a768be15cbf794c803e3b

$ python update.py --nodeps --base keystone \
    --dest-dir ../keystone \
    --modules db,db.sqlalchemy

This includes a fix where the keystone server would log a warning
that starts with

  This application has not enabled MySQL traditional mode ...

This change includes the following commits from oslo-incubator:

a1a8280 Fix excessive logging from db.sqlalchemy.session
dc2d829 Add lockutils fixture to OpportunisticTestCase
d10f871 Adapt DB provisioning code for CI requirements
5920bed Make db utils importable without migrate
9933bdd Get mysql_sql_mode parameter from config
96a2217 Prevent incorrect usage of _wrap_db_error()
20a7510 Add from_config() method to EngineFacade
fea119e Drop special case for MySQL traditional mode, update unit tests
a584166 Make TRADITIONAL the default SQL mode
5b9e9f4 Fix doc build errors in db.sqlalchemy

The above list was generated by doing the following in oslo-incubator:

 $ git log --oneline --no-merges \
     6ba44fd..0a3436fbcd69b7e0cd1a768be15cbf794c803e3b \
     openstack/common/db/ openstack/common/db/sqlalchemy

The keystone log shows that the last sync was 6ba44fd:

 $ git log -n1 --oneline --no-merges \
     keystone/openstack/common/db \
     keystone/openstack/common/db/sqlalchemy
 8f7b87b Sync db, db.sqlalchemy, gettextutils from oslo-incubator 6ba44fd

Closes-Bug: #1271706
Change-Id: If537ff5166b8e9a6fc18c570cdd2e44943faac9c
Filter out nonstring environment variables before rules mapping.

Before the requests environment is passed to the RuleProcessor, all
parameters that are not inheriting from the basestring type should
be filtered out.

Change-Id: I469107633abfa86232e1dc1f1bc64605cd888dc2
Closes-bug: #1291981
Merge "Sync db, db.sqlalchemy from oslo-incubator 0a3436f"
Merge "Filter out nonstring environment variables before rules mapping."