WBPS. Return funds

[AndreyKortosov]

User story

As a Creditor, I want to return invested money to the Investor.
As an Investor, I want to get back money and return CP tokens.

Acceptance criteria

1. The CR has an additional obligatory field - Interest rate. Type - float digits.
   1. If the Farmer requests $100 000 with an Interest rate of 5% for 1 year, after a period the Farmer should return $100 000 + 5% = $105 000.
2. The Farmer returns the money to the Creditor.
   1. The Creditor inputs that money via a Deposit request to the PR manager.
3. The Creditor changes the status of CR from Published to Closed.
   1. The SORA prepares CP tokens for claiming, the Investor should themselves claim the initial price of PRUSD + percentage.
      1. For example, the initial price of a CP token is $1000 and the interest rate is 5%, then at the end of CR the Investor will get $1000 + 5% = $1050.
   2. After claiming, the SORA pallet withdraws the CP token and burns it.