If --os-cacert was passed to the cli the following error was
triggered: "cafile must be None or a byte string". This is
because 'load_verify_locations' requires a byte string to
be passed in.
We fix this by explicitly converting the argument to a byte
string.
We do this in 'VerifiedHTTPSConnection' rather than sooner, eg
during arg handling, as it will no longer be required should we
move to a different http library (eg requests).
Fixes bug 1301849.
Change-Id: I9014f5d040cae9f0b6f03d8f13de8419597560cb
Stuart McLaren
6626f38cda