Implement `.update()` and `.digest()` flow

[memcorrupt]

Implement the specification similar to these below functions to allow new data to be continually streamed to the hashing function.

https://nodejs.org/api/crypto.html#cipherupdatedata-inputencoding-outputencoding
https://nodejs.org/api/crypto.html#cipherfinaloutputencoding

Relevant fuzzy.c functions:

• fuzzy_new (needs to be disposed with fuzzy_free)
• fuzzy_update
• fuzzy_digest