[arrow-vesting] Update Arrow-Vesting strategy to only count vested, unclaimed tokens

[bghughes]

Previously this strategy counted all tokens sitting on a vesting contract, including claimed ones. This led to weird behaviors and double counting. The Arrow community tasked me with iterating this strategy to only count vested Arrow that can be claimed but is unclaimed. This way, used with the balanceOf ERC20 strategy in voting, the snapshots will allow members to vote their vested Arrow, even if unclaimed, and there won't be incorrect accounting regarding stake on votes.

Shoutout to @daoio for the help.

Changes proposed in this pull request:

• Change arrow-vesting strategy to only count unclaimed Arrow tokens in a vesting contract

[bghughes]

For your review too @thomasgarrison who is the project admin

[ChaituVR]

Tagging @BrassLion as he is the author of the strategy

[ChaituVR]

There are two active proposals that use this strategy, better to wait until they are closed, or even better if we can just create a new strategy

https://snapshot.org/#/arrowair.eth/proposal/0xb8ec567d58521249365c2c6637ef6595c0ae4e6e9166e50d7dd07328f9777040
https://snapshot.org/#/arrowair.eth/proposal/0xc72c11d8cb5c83806d348872e9f7ee2a848cf9a4b8837c8d77a87fc7032e4661

[BrassLion]

LGTM. I had a quick look at the new strategy and the logic makes sense to me.

[thomasgarrison]

Thanks guys, this all looks good to me. @ChaituVR We're all good to merge this whenever you're ready. Since it's a bug fix, we wouldn't mind doing it while the current proposals are live

[ChaituVR]

@thomasgarrison Does it change the voting power of existing voters?

[thomasgarrison]

Yes. This is fixing a bug where voting power is being double counted if a voter has claimed $ARROW from a vesting contract. This is just now becoming an issue as cliffs have been reached. If that's problematic we can wait until the last proposal is done voting. I've asked everyone not to post any more proposals until this is merged in

[ChaituVR]

I see no open proposals now, so merging, Thanks for waiting ❤️