implement gofabric8 tenant update via calling the fabric8-tenant REST API

[jstrachan]

once this is supported
fabric8-services/fabric8-tenant#222

we should be able to implement the upgrade tenant via invoking this REST API, passing in the current openshift token

the tricky bit is gonna be how to detect where the f8tenant endpoint is; we don't yet put any marker anywhere in the tenant namespace to know where things are yet so until there's a place to discover these (e.g. via an annotation on the main users Project) we'd need to have this defined in an env var or CLI argument

once this is implemented we can remove the fabric8-tenant go dependencies completely!

[chmouel]

the tricky bit is gonna be how to detect where the f8tenant endpoint is; we don't yet put any marker anywhere in the tenant namespace to know where things are yet so until there's a place to discover these

What do you think about this implementation ? :

2107f47

[jstrachan]

LGTM :)