Adding a dummy global counter

Context

MR for introducing a dummy global counter which can be incremented through a manageer operation Increase_counter.

Draft PR, current state is:

• Add the manager operation in protocol Alpha (Increase_counter operation, Dummy_counter module in Alpha_context, storage under Dummy_counter_storage module)
• Add client command for injecting operation for this manager operation.
• Add an RPC call to check current counter value
• Add tests

Manually testing the 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