CLI: Allow using key name for --admin

[webmaster128]

The CLI field --from string Name or address of private key with which to sign allows me to use the local key alias. Now when I instantiate a contract with myself as the admin, I would like to do --from my_super_key --admin my_super_key without having to look up the address manually to avoid the risk of using the wrong one. However, when I try to do that I get

Error: admin: decoding bech32 failed: invalid separator index -1

Would that be possible to implement? Does it make sense?

[alpe]

👍 Sounds good to improve UX