Split turn in two stages: Proposal and voting

[peersky]

Current implementation of CVPP simplified in this repository and has shown negative feedback from users as it first requires everyone to submit next batch of proposals and only then will show feedback from previous round.

To fix this we must create flow where each turn consists of two distinct sections:

• Voting
• Proposing

This means that players no longer vote on "previous round proposals" but instead vote on current round.

The straightforward solution that is less work on a refactor side for us would be to

• Add CVPP wrapper to LibTBG that converts odd turns to a proposal stages and even a vote stage
• Add new game master facet method to submit proposals batch which can be done only to end odd turns in libtbg
• Convert endTurn method to submit votes batch, which can be used only to end even turns (in libtbg)
• Remove canEndTurn functionality from LibRankify and facets. Add canEndProposing, canEndVoting instead.
• Return proposing stage in to game state returns to allow dApp distinguish stage of a turn
• getTurn method should use CVPP wrapper instead of directly talking to LibTBG (divide libtbg by 2)
• Update readme, documentation