Create Reward Notifier For Transferring Tokens From A Treasury

[apbendi]

Create a reward notifier that can be used by DAO's that want to distribute rewards that are currently held in a treasury wallet. The assumption is that the DAO will:

1. Approve this reward notifier to transferFrom the total number of tokens to be distributed
2. Whitelist this reward notifier to call notify on the Staker instance

The Reward Notifier should:

• Have an immutable variable set on deployment which references the Staker instance
• Have an immutable variable set on deployment which references the Staker instance's reward token
• Be Ownable
• Have an owner updateable rewardAmount parameter which defines the number of tokens that are transferred for each reward distribution
• Have an owner updateable rewardInterval parameter which defines the minimum time between reward distributions
• Have an owner updateable rewadSource parameter which defines the address from which rewards are transferFromed
• Have a public notify method which:
  • Enforces that rewardInterval has elapsed since the last distribution
  • transferFrom's the tokens to the Staker instance
  • Calls notifyReward on the Staker