TIP-019 Maintain tetuBAL liquidity using part of the voting power

Proposing a dynamic strategy to maintain high liquidity using part of tetuBAL's voting power.

This strategy revolves around a logic: if the tetuBAL-BAL/ETH pool holds less than X% of the total tetuBAL supply, the voting power of pure tetuBAL decreases by Y%.

The decreased power generates benefits that are split into two:

1. 50% adds liquidity to the pool.
2. 50% is sent to veTETU holders as incentives for the tUSDC vault (similar to the xtetuBAL part).

We suggest X=15% and Y=30%. Thus, veTETU will consistently receive 15% of the tetuBAL incentives.

If there's no pool liquidity, the reduction is maxed, encouraging tetuBAL holders to maintain liquidity. It's more profitable to vote for the pool a little and gain more power in the next round.

If liquidity meets expectations, there's no power reduction for tetuBAL, and veTETU gets its share of incentives from the tetuBAL in the pool (as it currently operates).

Furthermore, for aligning numbers, xtetuBAL will also be affected by this change but in a bit more complex way.

Currently, xtetuBAL has a 5% perf fee used for buybacks tetuBAL. To keep possible differences with pure tetuBAL, we will implement the following logic in the distribution script: xtetuBAL should have the same fee as pure tetuBAL but minimal 5% 5% will always go to tetuBAL buybacks remaining % will be split 50/50 by the above-described logic.

For example, if pure tetuBAL has the cut 15% then 5% will be used for buybacks, 5% for increasing liquidity and 5% will go to veTETU.

You can track current allocations here (we count all Balancer balance as the pool allocation) https://polygonscan.com/token/0x7fC9E0Aa043787BFad28e29632AdA302C790Ce33#balances