[r=wallyworld],[bug=1246320] [r=][bug=1246320][author=wallyworld] Azure now requires certain requests to the management api to have an updated version number in the header. Such changes are supposed to be backwards compatible but msft failed not to break existing applications. This branch includes the new api version. It also base64 encodes customdata sent with the request, as this also appears to have changed from underneath us.
With these changes, juju bootstrap now completes and the bootstrap instance spins up. Previously it would have errored part way through bootstrap. There still may be an issue with cloud-init completing properly but if this is the case, it appears to be a separate issue and I'd like to land this branch to allow others with Azure credentials to help debug.