BSIP - Market Fee Backed Asset (MFBA)

## Abstract
Market Fee Backed Asset (MFBA) is a SmartCoin introduced by this BSIP.
The main idea of a MFBA is to provide opportunity for the Assets Owners to automatically share revenue received from trading operations (Market Fees) to the holders of the MFBA in proportion of the owned amount of the MFBA.

## Motivation
By implementing this proposals, we let Asset Owners an opportunity to use their assets as profit-sharing assets.
Distribution of fees will be conducted automatically (in a pre-defined period of time). Such functionality is currently not available in the blockchain.

## Specifications
**Market Fee Backed Asset Definition**
New attribute of the SmartCoin - "MFBA" attribute becomes available for the users. Asset for which "MFBA" option is available will be called MFBA Asset.

**Tied assets**
Issuer of the MFBA Asset will be able to tie his/her other assets (one or many) to the MFBA Asset. Tied assets cannot become MFBA.

**Dividends**
Market Fee, received from the trading operations of the tied assets will be distributed between holders of the MFBA Asset according to the stake of the MFBA Asset that holders have.
Issuer of the MFBA Asset must be able to set share of the Market Fee, that will be distributed to the holders of the MFBA Asset as a parameter (MFBA share, %).
Whatever is left after distribution to the MFBA holders will be left for the Asset Owner.
Funds currently in the open orders will not be included in the MFBA share.

**Blacklist and Whitelist**
Whitelist and blacklist (configurable by the UIA Issuer) could provide control over who is eligible to earn dividends.

**Dividends Distribution Process**
Distribution will be performed in a set period of time. Period of time must be set by the MFBA Issuer (minimal available interval must exist).
Market Fee of the tied assets is accumulated during this period. At the end of the period fee is distributed to the MFBA holders' "special balances" and to the MFBA Issuer "special balance".
After that MFBA holders and MFBA Issuer can claim the fees.

**Dividends Distribution Process Restrictions**
Distribution must be performed starting from the user, that has the biggest share of the MFBA Asset.
Users for which amount to be transferred is less, than should be accrued, will not receive their share of Market Fee.

## CORE TEAM TASK LIST
- [ ] Evaluate / Prioritize Feature Request
- [ ] Refine User Stories / Requirements
- [ ] Define Test Cases
- [ ] Design / Develop Solution
- [ ] Perform QA/Testing
- [ ] Update Documentation

No implementation files, tests, or entry points are named. Start by refining the MFBA user stories and requirements, then define test cases for tied assets, fee shares, eligibility lists, distribution intervals, special balances, and claiming. Done means the design is agreed, implementation work is scoped, and documentation and QA requirements are defined.

Written by the indexing model from the issue text.