[Cirrus] Add IsExpired status to Poll

[quantumagi]

See https://app.clickup.com/t/a11fjz,

[fassadlr]

@quantumagi I'm mostly good with this, however, do we need to do this via BIP9 as opposed to an activation height? All masternodes are required to upgrade when we upgrade the SidechainMasternode branch, so it is kinda something we control. In other words, if we push to that branch and they have to restart their MN due to an windows update, they are forced to upgrade.

Perhaps an activation height is just easier?

[quantumagi]

@fassadlr , The BIP9 activation would just make the upgrade a bit smoother. Otherwise, if only a few nodes upgrade straight away then they will be faced with errors due to federations that differ from what is expected by the non-upgraded majority. If we use BIP9 then it will eventually only be the non-upgraded 10% that will face errors that will require them to upgrade as well. That said, it may still depend a lot on how the upgrade is managed. WDYT?

BTW we could add the activation height stuff as a separate PR and remove a few files from this one. See #713.

[fassadlr]

@fassadlr , The BIP9 activation would just make the upgrade a bit smoother. Otherwise, if only a few nodes upgrade straight away then they will be faced with errors due to federations that differ from what is expected by the non-upgraded majority. If we use BIP9 then it will eventually only be the non-upgraded 10% that will face errors that will require them to upgrade as well. That said, it may still depend a lot on how the upgrade is managed. WDYT?

BTW we could add the activation height stuff as a separate PR and remove a few files from this one. See #713.

The masternode users are generally very active with regards to keeping their nodes upgraded and like I said, we control the upgrade by indirectly forcing them to upgrade when they restart their node. This can be due to Windows updates etc. If we set an activation height 2 weeks from release and announce in the channel daily, 99% of the guys will be upgraded by the time activation happens. I know that the other guys prefer activation heights as well, so perhaps lets move it to that? WDYT?

[fassadlr]

Otherwise, the PR looks 👍

[quantumagi]

@fassadlr , Sounds good. I've made the change.

[fassadlr]

We just need to set the activation heights and agree on the poll expiry period 👍