Figure out how to refresh OpenShift API token automatically

[tzumainn]

We have a way of installing OpenShift programatically through the Assisted Installer API, as document at https://esi.readthedocs.io/en/latest/usage/openshift.html#using-the-python-esiclient-cli. However, the process involves a token that expires every 10 minutes. The documentation explains this and details how to continue the installation; however, it would be better if we could either have a longer-lasting token or if there was a way to refresh it automatically.

You can see examples of the API commands we issue in https://github.com/CCI-MOC/python-esiclient/blob/master/esiclient/v1/cluster/openshift.py. Working on this issue will presumably require taking some of that code to run API commands; however, you should not need to run the OpenStack/Ironic commands.