Create a bloc, a repo and pertinent values, entities, interfaces and extra logic to handle assigning commitments, editing their values and adding blocks.

[dromerolovo]

The state of this bloc should be a List<Commitments> and its initial state should be empty.

Should implement the following events:

• Adding a commitment
• Updating a commitment

Consider that the state of the bloc should be immutable so instead of calling the following method to add commitments List.add() is better to add a commitment like this: [...state.commitments, event.commitment]

And to update a commitment:

      var newCommitments = commitments.map((commitment) {
        if(commitment.id == event.commitment.id) {
          return event.commitment;
        }  else {
          return commitment;
        }
      }).toList();

[dromerolovo]

Done in feat/commitments-form branch