Validator metadata update and queries

[alpe]

• Resolves Expose new contract functionality commands #87
• Resolves Update validator Meta data #57

This PR adds another step in the integration of the PoE module in the app stack

CLI updates

• Queries

tgrade q poe:

  unbonding-period Query the global unbonding period
  validator        Query a validator
  validators       Query for all validators

• Commands

tgrade tx poe

  edit-validator   edit an existing validator account

Not included:

• State export Support validator state export #95
• Contract staking query support Support staking queries for contract #96
• Contract staking message support Support staking messages for contracts #97

[ethanfrey]

Looks good. This review was mainly stream of consciousness of my reactions.

Many places are just my question as to how things work.
A few suggestions to change (which may be ignored if I understand incorrectly).

The changes look big and generally proper. I will look how these build in the other PR now.

[ethanfrey]

Looks like you addressed my concerns.

Let's merge this and move onto the next ones.