Create Vesting smart-contract

[zxcat]

1. Requirements

1. Use safe arithmetics to increment/decrement assets to prevent overflow (asset operator +=, -= are safe)
2. Token resides in system token contract, it can be issued while emission. Token transferred to polls with normal transfers.
3. Vesting must have calculated total amount (total_vesting), valid in each action (update it on vesting amount change: conversion/withdraw/burn). Vesting is not liquid, so if implement it based on system token contract, additional restrictions must be added (preventing direct transfers).

2. Configurable properties (per Token)

1. Vesting Withdrawal
   1. Number of intervals
   2. Seconds in interval
   3. Min amount to withdraw
   4. Min balance amount to allow withdraw
2. Voting power (Power considered as resource)
   1. Capacity (100%)
   2. Regeneration seconds (5 days)
   3. Max value used per vote (0.5%)
3. Delegation
   1. Min amount
   2. Min seconds
   3. Max interest (%)
   4. Seconds to return

3. Methods

1. Current price
   • Args: (token)
   • Returns: total_vesting / total_vesting_fund_token
2. Convert Token to Vesting
   • Args: (from, to, token_amount)
3. Token to Vesting with delegators reward
   • Args: (from, to, token_amount)
4. Withdraw Vesting to Token
   • Args: (from, to, vesting_amount)
5. Burn Vesting
   • Args: (owner, amount)
6. Delegate
   • Args: (delegator, delegatee, amount, rate)
7. Return Delegation
   • Args: (delegator, delegatee, amount)
8. Consume Power
   • Args: (power_amount)
   • Returns: used power in vesting