DAL/Node: fetch constants from node

Context

The dal node currently has hardcoded values for DAL constants.

In this MR, we connect the DAL node to a Tezos Node and add a plugin mecanism. At start-up, the DAL Node now:

• Connects to a given endpoint
• Awaits for a supported protocol (implementing the plugin)
• calls the constants rpc to fetch dal constants
• Load DAL node crypto using those constants.

fixing #3314 (closed)

Manually testing the MR

Tests are currently blocking and will come in a following MR.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR