Recursive

[Al-Kindi-0]

This PR implements a proposed modification to the FRI verifier in order to make it more "recursion friendly". Ideally, the FRI prover should remain untouched and a parser should be implemented in order to turn the currently generated FRI proofs into a format that the FRI verifier in this PR can work on. However, the FRI prover is also modified as it was better, understanding wise, and easier during the development of the new verifier.
A few points worth noting:

1. New data structures, based on the already implemented ones, are introduced. Little thought was given to the efficiency or code esthetics but this should be considered once we settle on the core ideas.
2. In some places, especially functions on queries, a vector of inputs consisting of only one variable is used in order to be able to use the already existing helper functions. Clearly this is unnecessary and these portions should be adapted appropriately.
3. There are still remnants of BatchMerkleProof's in the code, and again, this is kept only to make some old parsing functions work as is and will be changed to the functions that verifies a single Merkle proof.