Updating the Operation class following the meeting with the quantum s…

[alexanderivrii]

…ynthesis team; adding tests to test_operation

Summary

Updating the Operation class based on the discussion with the quantum synthesis team and notes from Jake.

Adding tests to test operation that check:

1. we can instantiate various classes that have Operation interface and they have the expected name, num_qubits and num_clbits.
2. we can add such objects to a QuantumCircuit

Details and comments

The QuantumCircuit itself is still not an Operation, as we have agreed we will add this functionality when we get a use-case for that.

The soon-to-follow (but a different) PR will be to make LinearFunction of type Operation and not of type QuantumCircuit