Refactor into mono repo

[yknl]

→ auth
    All authentication related API
    `userSession`, `signIn`
→ storage
    All Gaia related API 
    `putFile`, `getFile` etc.
→ profile
    Functions used to manipulate user profiles on BNS
→ keychain
    Stacks key generation, manipulation and addresses
    HD wallet derivation for account and wallet
→ transactions
    Transaction building API in `stacks-transactions`
→ network
    API for communicating with Stacks node and sidecar
    Including transaction broadcast, nonce, balance and fee estimation currently part of transactions lib.
→ encryption
    All existing encryption functions in blockstack.js
→ cli
    The stacks CLI, superseding the Blockstack CLI

[hstove]

I would recommend also merging:

• zone-file
• jsontokens

We should also strongly consider merging all of clarity-js-sdk.