Refactor EVM prover code to support distinct statements

[Nashtare]

For the sake of maintaining both type-1 and type-2 provers (and possibly additional variants along the way), with minimal code duplication, as well as to facilitate any upgrade that would affect both versions, we need to prover to be modular enough and activate one instance over another through feature flags.

In particular, with respect to type-2, we need:

• identify the distinct Kernel parts that need distinct handling
• unify the entry / exit point of pieces that would have distinct logic (for instance mpt_trie vs smt_trie), i.e. identical stack modifications
• tweak the proving code (cf extra PoseidonStark table and CTLs for instance). We may want to have a dedicated constant module with distinct versions inside, instead of the hardcoded (and possibly changing) values here and there (cf const NATIVE_INSTRUCTIONS: [usize; 13] for instance).

[Nashtare]

For this, I think we could do the work off the type2/hermez and against that branch, so that it can then be directly merged to main.

[Nashtare]

Assigning this to myself, though I'll wait for #31 to be merged into develop, then rebase #150 on top on top and start this work from it.

[Nashtare]

Replaced by #561