Fix some typos in neutron/db and IBM SDN-VE plugin

For example, in neutron/db/agents_db.py, db_plugin_base_v2 should be changed to db_base_plugin_v2.
There is no bug or blueprint related to this fix.

Change-Id: I0d348d92c9c32f172d1e505cf660aed4d064a440
Synced jsonutils from oslo-incubator

The sync includes change that makes sure we get unicode-only dicts from
jsonutils no matter which json module implementation is selected.

The latest commit in oslo-incubator:
- 0f4586c0076183c6356eec682c8a593648125abd

The sync adds a new 'strutils' module that is now used in jsonutils.

Change-Id: Ic815ca3df94c33edec9104172048b2cd94b92e3f
Closes-Bug: 1314129
Merge "Fix some typos in neutron/db and IBM SDN-VE plugin"
Merge "Synced jsonutils from oslo-incubator"