Add unittests for faultwrap middleware

Partially implements bp exception-formatting

Change-Id: Ib57ce625775e222e5b42b22c10687bce7b63d26d
db: Remove deprecated assert_unicode attribute

Remove deprecated assert_unicode sqlalchemy attribute,
removed in sqlalchemy 0.8.0. The deprecation is described
at:

http://docs.sqlalchemy.org/en/latest/changelog/changelog_08.html#change-ad44af79c886d1bb283042deb64f9cbe

Change-Id: I874be66948fc296bc6afe7f731dc4731645f0fbe
Signed-off-by: Chuck Short <chuck.short@canonical.com>
Merge "Add unittests for faultwrap middleware"
Merge "db: Remove deprecated assert_unicode attribute"