prepare for deprecating with README and MIGRATING.md (#177)

* prepare for deprecating with README and MIGRATING.md

* fix: update capitalization

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: add name, formatting

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: plugin capitalization

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: formatting for brand new users section

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: caps + period

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: bullet point + formatting

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: second bullet point

Co-authored-by: rstavchansky <rachael@netlify.com>

* fix: caps build plugin

Co-authored-by: Jason Lengstorf <jason.lengstorf@netlify.com>
Co-authored-by: rstavchansky <rachael@netlify.com>

Author: 3 people

MIGRATING.md

@@ -0,0 +1,17 @@
+## Migrating to Essential Next.js Plugin
+
+This guide is to assist `next-on-netlify` users in their migration to Netlify's [Essential Next.js Build Plugin](https://github.com/netlify/netlify-plugin-nextjs).
+
+Please visit [this issue](https://github.com/netlify/next-on-netlify/issues/176) to ask questions about migrating and/or the deprecation of `next-on-netlify`.
+
+### Existing NoN users
+
+1. [Uninstall](https://docs.npmjs.com/uninstalling-packages-and-dependencies) `next-on-netlify`.
+2. Remove the `"postbuild": "next-on-netlify"` script from your `package.json`.
+3. Get the Essential Next.js plugin.
+    - For new Next.js sites on Netlify, the plugin will be automatically installed. You can [opt out of the plugin](https://docs.netlify.com/configure-builds/build-plugins/#remove-a-plugin) by visiting the **Plugins** tab for your site in the Netlify UI.
+    - For existing sites on Netlify, follow the manual installation instructions in the [plugin README](https://github.com/netlify/netlify-plugin-nextjs#installation-and-configuration), which explains UI-based and file-based installation.
+
+### Brand New Users
+
+Deploy a new Next.js site to Netlify! Your site will automatically build with the plugin. You can [opt out of the plugin](https://docs.netlify.com/configure-builds/build-plugins/#remove-a-plugin) by visiting the **Plugins** tab for your site in the Netlify UI.

README.md

@@ -17,23 +17,13 @@
 
 `next-on-netlify` is a utility for enabling server-side rendering in Next.js on Netlify. It wraps your application in a tiny compatibility layer, so that pages can use Netlify Functions to be server-side rendered.
 
-- Build plugin [@netlify/plugin-nextjs](https://github.com/netlify/netlify-plugin-nextjs)
-- [Plugin npm package](https://www.npmjs.com/package/@netlify/plugin-nextjs)
-
-## Next on Netlify Roadmap
-
-The future of Next.js on Netlify is growing beyond `next-on-netlify`. The recommended path forward is to install [@netlify/plugin-nextjs](https://github.com/netlify/netlify-plugin-nextjs) - a build plugin released and supported by the team behind `next-on-netlify`.
+## Deprecating next-on-netlify
 
-The plugin relies on `next-on-netlify` but offers a smoother experience, including:
+We are deprecating `next-on-netlify` in favor of Netlify's [Essential Next.js Build Plugin](https://github.com/netlify/netlify-plugin-nextjs). Please visit [this issue](https://github.com/netlify/next-on-netlify/issues/176) to learn more about the deprecation of `next-on-netlify` and ask any questions. You can also visit our simple [Migration doc](https://github.com/netlify/next-on-netlify/blob/main/MIGRATING.md) for assistance migrating to the plugin.
 
-1. one-click, zero-config installation
-2. allowing custom functions and publish directories
-
-See the [plugin's README](https://github.com/netlify/netlify-plugin-nextjs#readme) for more information. Our team's end goal is to make the Next.js on Netlify experience as seamless as possible.
-
-Note: since `next-on-netlify` will remain the primary source of logic for Next.js on Netlify, the existing `next-on-netlify` setup will continue to work for users who prefer manual installation and configuration.
+- Build Plugin [@netlify/plugin-nextjs](https://github.com/netlify/netlify-plugin-nextjs)
+- [Plugin npm package](https://www.npmjs.com/package/@netlify/plugin-nextjs)
 
-The plugin can be found on [npm here](https://www.npmjs.com/package/@netlify/plugin-nextjs).
 
 ## Table of Contents