Ranked collective `Add`+`Remove` origins (#3212)

Superseeds https://github.com/paritytech/polkadot-sdk/pull/1245  

This PR is a migration of the
https://github.com/paritytech/substrate/pull/14577.

The PR added associated types (`AddOrigin` & `RemoveOrigin`) to
`Config`. It allows you to decouple types and areas of responsibility,
since at the moment the same types are responsible for adding and
promoting(removing and demoting). This will improve the flexibility of
the pallet configuration.

```
/// The origin required to add a member.
type AddOrigin: EnsureOrigin<Self::RuntimeOrigin, Success = ()>;

/// The origin required to remove a member. The success value indicates the
/// maximum rank *from which* the removal may be.
type RemoveOrigin: EnsureOrigin<Self::RuntimeOrigin, Success = Rank>;
```
To achieve the backward compatibility, the users of the pallet can use
the old type via the new morph:

```
type AddOrigin = MapSuccess<Self::PromoteOrigin, Ignore>;
type RemoveOrigin = Self::DemoteOrigin;
```

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: PraetorP <praetorian281@gmail.com>
Co-authored-by: Pavel Orlov <45266194+PraetorP@users.noreply.github.com>