Implement RFPs feature on contract

[PolyProgrammist]

• [ ] Create Timeline type for RFP
• [ ] Create body for RFP-proposal (including links to RFP and github project address)
• [ ] Create body for RFP (including it's timeline, selected proposal, submission deadline, subset of devhub proposal's fields)
• [ ] Implement logic for using different body type including devhub proposals
• [ ] Add access control data including rules and moderators
• [ ] Create deployment action on Github
• [ ] Create all the methods for RFPs and RFP-proposals
• [ ] Add tests for everything
• [ ] Test manually in production

[PolyProgrammist]

Moved to bos repo