Update redis library to >=2.10.0

Tooz is using this library and is depending on a version that
has exceptions added in 2.10.0 so in order to avoid conflicts
we should bump up the redis to be at least that version. This
avoids mishaps later with other users that could be depending
on versions <2.10.0

Change-Id: Ia8e58f8cb6a19d2a12846a6a8f0e2e313d48f9a0
Merge "Update redis library to >=2.10.0"