v7 migration guide (#1070)

* v7 migration guide

* Update sidebars.json

* Create v6-to-v7.md

* Update v6-to-v7.md

README.md

@@ -117,6 +117,10 @@ Quick links
 
 [CLI commands and configuration](https://npmpackagejsonlint.org/docs/cli) | [Node.js API](https://npmpackagejsonlint.org/docs/api) | [Integrations](https://npmpackagejsonlint.org/docs/integrations)
 
+## Migrating from v6.x.x to 7.x.x
+
+Please see the [migration guide](https://npmpackagejsonlint.org/docs/v6-to-v7).
+
 ## Migrating from v5.x.x to 6.x.x
 
 Please see the [migration guide](https://npmpackagejsonlint.org/docs/v5-to-v6).

website/docs/v6-to-v7.md

@@ -0,0 +1,12 @@
+---
+id: v6-to-v7
+title: v6 to v7 Migration Guide
+---
+
+v7.0.0 Migration Guide
+
+> FYI: v7 drops support for Node 14. If you need support for versions of Node that have reached EOL, please use v6.
+
+Properties to [`prefer-property-order`](https://npmpackagejsonlint.org/docs/rules/package-json-properties/prefer-property-order/) rule. Please see [`#1055`](https://github.com/tclindner/npm-package-json-lint/pull/1055). Thank you, @regseb!
+
+Please see the [release notes](https://github.com/tclindner/npm-package-json-lint/releases/tag/v7.0.0) for additional changes introduced in v7.0.0.

website/sidebars.json

@@ -19,6 +19,7 @@
       "related-projects"
     ],
     "Migration Guides": [
+      "v6-to-v7",
       "v5-to-v6",
       "v4-to-v5",
       "v3-to-v4",