UpgradeImpact
=============
The Connection class now enables retry_on_ratelimit by default.
If you need to return to the old behavior, explicitly pass
retry_on_ratelimit=False as a keyword arg.
The SwiftService class will now enables the retry_on_ratelimit option by
default. If you need to return to the old behavior, explicitly set it to
false in your options dict.
Change-Id: I3221fda84f0b8031c50128aa600e2c19deb5b102
a1d2f31131