BIG-IQ licensing should support multiple BIG-IQ bigIqHost for HA

[jgruber]

Is your feature request related to a problem? Please describe.

When deploying BIG-IQ in cloud environments, the HA for BIG-IQ is not always a trivial deployment. It is a problem to setup a VIP without going into cloud failover route support, etc.

Seeing that Licensing Manager is THE fundamental use case for BIG-IQ, it would be great if DO License class supported a single or list of bigIqHost attempt for licensing. If an preceding BIG-IQ instance is not reachable (TCP time-out or HTTP error), the next bigIqHost should be tried. If the BIG-IQ are setup as a redundant pair, this should work nicely.

Describe the solution you'd like

DO License class could take a single or a list of bigIqHost to attempt licensing.

It is fine to have the requirement that the rest of the License class attributes remain unchanged. This would mean the same bigIqUsername, bigIqPassword, and licensePool must exist on all bigIqHost (s) in the list.

Describe alternatives you've considered

Messy public cloud routing redundancy setup.

Additional context

None