Draft new proposal with finer milestones from #20

[ehildenb]

After discussions with the Polkadot team, we've decided that fleshing out the approach described in #20 is more beneficial long term to both (1) the KWasm verification ecosystem, and (2) interests in verifying the KWasm code for Polkadot itself.

We'll re-draft the proposal with refined milestones, including:

• Spec generation at the Wasm level via fuzzing/rule fusion,
• Refinement proofs from high-level K spec to KWasm,
• Completion proofs of the generated specs,
• Assisting Polkadot devs in producing/maintaining the high-level specs of Polkadot itself.

[ehildenb]

#42 is the new milestones