FEATURE: migrate functionality from manta to cama

[Masber]

Isolate and port the functionality below from manta to cama:

• command to check if user has access to cluster/nodes --> This is very important because we may discard this and leverage this functionality to TAPMS, this means we should be able to isolate this code ASAP.
• fetch configuration details based on HSM group
• fetch configuration details based on list of nodes
• fetch session details based on HSM group
• fetch session details based on list of nodes
• fetch bos session templates based on HSM group
• fetch bos session templates based on list of nodes

The tasks above involves the following actions in cama:

• create new endpoints
• mesa integration
• create new structs

This ticket is related to https://github.com/eth-cscs/cama/issues/4