Calculate projected APRs

Projected APRs are determined by taking the current Balancer APRs & multiplying them by the pool boost. The AURA APR is then calculated by taking the estimated boosted BAL yield per year and passing it to the getAuraMintAmount() function to get an estimated AURA yield per year.

To pull the current Balancer APRs, Aura uses Balancer’s balancer-sdk (https://github.com/balancer-labs/balancer-sdk/)