Decouple Gemini from Interleaving #1293

Currently, GeminiProver populates a single vector of claims that optionally contains 2 interleaving-related claims at the end. When parsed by ShplonkProver, the interleaving claims are multiplied by $\nu^{d}$ and $\nu^{d+1}$, where $d$ is the circuit size without padding, instead of $\nu^{C}$ and $\nu^{C+1}$. Not critical at all, but would be nice to separate optional interleaving logic fromm the main Gemini protocol.