Proposal: remove self-staking requirement

[zjshen14]

It seems not necessary to enforce the delegate account to self stake, which is not friendly to asset custody. People who manages the delegate profile, reward distribution doesn't need to be the one who manages the asset.

If we do need a primary responder (e.g., slashing for doing bad things) for a delegate, this could be a different address, similar to operator address.

[dustinxie]

Self-stake purpose is (like you mentioned) "need a primary responder (e.g., slashing for doing bad things)", if we use a different address, it is still "self-stake" but to a different address? Put it another way, what are the benefits of using a different address to receive the "self-stake" token?