[Task] Figure out how to deprecate nomicon.io

[gagdiez]

Background

We still have too many documentation sites, a good idea would be to remove nomicon.io and establish our docs site as:

• near-nodes.io -> to be were we explain how to setup a validator node / RPC node
• https://near.github.io/nearcore/ -> to be the low level explanation for protocol developers
• docs.near.org -> to be were we teach high level concepts of NEAR, show developers how to build cool stuff using NEAR, and guide everyone to the right place

User Story

Acceptance Criteria

Resources & Additional Notes

No response

[bucanero]

Review of current Nomicon docs has been completed:

• https://docs.google.com/spreadsheets/d/1SdDwlEaxSN9haPrvt0F7bspIWQCEVtmGJtM7rgj-Dpo/edit?gid=0#gid=0
• Proposals section is outdated, which will be dropped
• Standards section that mirrors current NEPs will be dropped, so the original NEPs are the single source of truth.
• Protocol specs will be merged with nearcore docs.

From discussion and feedback with Bowen and Josh:

• nearcore mdBook site will be updated, including protocol specification docs from Nomicon.io
• https://near.github.io/nearcore/ site will be hosted at nomicon.io
• remaining pages will be added to docs.near.org