Add Full Quorum Tests

Added some tests to bring a full quorum online (of 4) and see that smoothly enter synchronization, which they appear to.

The way that Sibling.Active has changed, so that the variable is Sibling.Status, where ^byte(0) is Inactive, 0 is active, and any other number is passive, where the number indicates how many blocks until the sibling is automatically toggled as active.
Having `Active()` and `Inactive()` use the Status byte is slightly confusing. From their names, one might assume that they are tied to a boolean, which makes the conditional `!Active() && !Inactive()` seem nonsensical. Not saying this needs to be changed, just that it might throw people off.