Alpha Improvements

[Yakuhito]

Improvements:

• Better precision: Current round's Reward_Info numbers now use mojos * PRECISION as a unit. This means that, for 1 year epochs, you can have up to 550 billion (10**(log10(2 ** 64) - log10(60 * 60 * 24 * 365)), assuming a precision of 2**64) active shares and 1 mojo worth of tokens will be distributed if someone were to call 'sync' every second. The units are changed from mojos to mojos * PRECISION in add_incentives, new_epoch and from mojos * PRECISION to mojos in initiate_payout, remove_entry, unstake.
• Liquidity distributors (liquidity farms): Stake CATs instead of NFTs to earn rewards. This is a different type of distributor - a distributor's type is set at launch and immutable. Staking weight equals CAT amount, and users can unstake at any time.
• NFTs from DL: An alternative NFT reward distributor where any NFTs from a curated datastore may be staked. NFTs may be assigned different weights.
• Slot consolidation: When staking assets, they can all be consolidated in the same slot. This is especially important for NFTs - instead of creating n slots for n NFTs, one slot can be used per custody puzzle hash (address/user). This change also limits the number of payout CAT coins created - instead of one coin per NFT, users will receive one coin per slot.