Migrate to CC API V3

[gberche-orange]

CC API V2 deprecation draft plan has been published. A 6 month overlap is planned by the time the CF CLI is not using CC API V2 anymore. See related mailing list thread at https://lists.cloudfoundry.org/g/cf-dev/message/8494?p=,,,20,0,0,0::Created,,v2+deprecation,20,2,0,29809681

Related migration notes from stratos at https://github.com/cloudfoundry-incubator/stratos/blob/v2-master/docs/cf-api-v3.md