Doc on michelson-encoder and michel-codec

[jevonearth]

• [x] Cover basics and advanced useage of the michelson-encoder package.
• [ ] Cover Taquitos representation of Michelson types
• [ ] How they might be used for examples such as form generation. - blocked by the type generation work.

[jevonearth]

Related #418

[Innkst]

https://tezostaquito.io/docs/michelson_encoder covers basic and advanced usage

[roxaneletourneau]

Michelson-encoder: Add documentation on the rules of what makes an entrypoint