TO: Szegoo FOR: cumulus#2294 (medium)<br/>

Send a batch of dispatch calls.

May be called from any origin except `None`.

- `calls`: The calls to be dispatched from the same origin. The number of call must not
  exceed the constant: `batched_calls_limit` (available in constant metadata).

If origin is root then the calls are dispatched without checking origin filter. (This
includes bypassing `frame_system::Config::BaseCallFilter`).

# <weight>
- Complexity: O(C) where C is the number of calls to be batched.
# </weight>

This will return `Ok` in all circumstances. To determine the success of the batch, an
event is deposited. If a call failed and the batch was interrupted, then the
`BatchInterrupted` event is deposited, along with the number of successful calls made
and the error of the failed call. If all were successful, then the `BatchCompleted`
event is deposited.

- Problem Statement: The problem is that there is a need for a referendum on Polkassembly.
- Audience: The intended audience is the Polkassembly community.
- Significance: The significance of the problem is that it allows the community to have a say in important decisions.
- Proposed Solution: The proposed solution is to hold a referendum on Polkassembly.
- Expected Outcomes: The expected outcome is to gather community input and make decisions based on the referendum results.

Requested: 0.50 undefined

Referenda #199