cli: make all commands use --from

[ValarDragon]

Currently gov submit-proposal has --proposer instead of --from
Currently stake delegate has --address-delegator instead of --from.

I think this is incredibly confusing. For any transaction where this field should be populated by "Who is sending the transaction", the flag should always support the alias --from. I think this should support just --from, and not the alternatives.

[fedekunze]

Same with gov vote that has --voter

[rigelrozanski]

I could work on this this week unless @ValarDragon wants to?

[ValarDragon]

I have no plans to work on this. (I'm trying to move to doing more tendermint things) Please go ahead!