restructure Appendix I: "Resources" -> "Useful Links" page, group links

_SUMMARY.md

@@ -241,19 +241,7 @@
 
 ## Appendix I - Resources
 
-* [Introduction](resources.md)
+* [Useful Links](appendix/resources/useful_links.md)
-* [IntelliJ Community Edition on GitHub](https://github.com/JetBrains/intellij-community)
-* [IDE Settings, Caches, Logs, and Plugins](https://intellij-support.jetbrains.com/hc/en-us/articles/206544519-Directories-used-by-the-IDE-to-store-settings-caches-plugins-and-logs)
-* [IntelliJ Plugins](https://github.com/JetBrains/intellij-plugins)
-* [IntelliJ Platform Artifacts Repository](reference_guide/intellij_artifacts.md)
-* [IntelliJ Scala Plugin](https://github.com/JetBrains/intellij-scala)
-* [Gradle IntelliJ Plugin](https://github.com/JetBrains/gradle-intellij-plugin)
-* [IntelliJ SDK Documentation](https://github.com/JetBrains/intellij-sdk-docs)
-* [IntelliJ Plugin Verifier](https://github.com/JetBrains/intellij-plugin-verifier)
-* [IntelliJ Plugin Developers Gitter](https://gitter.im/IntelliJ-Plugin-Developers/Lobby)
-* [Community SDK Forum](https://intellij-support.jetbrains.com/hc/en-us/community/topics/200366979-IntelliJ-IDEA-Open-API-and-Plugin-Development)
-* [Open Source Plugins](https://plugins.jetbrains.com/search?correctionAllowed=true&pr=&orderBy=name&search=&should_have_source=true)
-* [Kotlin Reference](https://kotlinlang.org)
 
 ## Appendix II - Breaking API Changes
 

appendix/resources/useful_links.md

@@ -1,19 +1,25 @@
 ---
-title: Resources
+title: Useful Links
+redirect_from:
+  - /resources.html
 ---
 
 The following links represent useful resources for working with the _IntelliJ Platform_ and creating plugins.
 
-* [IntelliJ Community Edition on GitHub](https://github.com/JetBrains/intellij-community)
+### Repositories
-* [IDE Settings, Caches, Logs, and Plugins](https://intellij-support.jetbrains.com/hc/en-us/articles/206544519-Directories-used-by-the-IDE-to-store-settings-caches-plugins-and-logs)
+* [IntelliJ SDK Documentation](https://github.com/JetBrains/intellij-sdk-docs)
+* [IntelliJ Community Edition](https://github.com/JetBrains/intellij-community)
 * [IntelliJ Plugins](https://github.com/JetBrains/intellij-plugins)
-* [IntelliJ Platform Artifacts Repository](reference_guide/intellij_artifacts.md)
 * [IntelliJ Scala Plugin](https://github.com/JetBrains/intellij-scala)
+* [Open Source Plugins](https://plugins.jetbrains.com/search?correctionAllowed=true&pr=&orderBy=name&search=&should_have_source=true)
+
+### Tooling
+* [IDE Settings, Caches, Logs, and Plugins](https://intellij-support.jetbrains.com/hc/en-us/articles/206544519-Directories-used-by-the-IDE-to-store-settings-caches-plugins-and-logs)
+* [IntelliJ Platform Artifacts Repository](reference_guide/intellij_artifacts.md)
 * [Gradle Plugin for Grammar-Kit](https://github.com/hurricup/gradle-grammar-kit-plugin)
 * [Gradle IntelliJ Plugin](https://github.com/JetBrains/gradle-intellij-plugin)
-* [IntelliJ SDK Documentation](https://github.com/JetBrains/intellij-sdk-docs)
 * [IntelliJ Plugin Verifier](https://github.com/JetBrains/intellij-plugin-verifier)
-* [IntelliJ Plugin Developers Gitter](https://gitter.im/IntelliJ-Plugin-Developers/Lobby)
+
+### Help
 * [Community SDK Forum](https://intellij-support.jetbrains.com/hc/en-us/community/topics/200366979-IntelliJ-IDEA-Open-API-and-Plugin-Development)
-* [Open Source Plugins](https://plugins.jetbrains.com/search?correctionAllowed=true&pr=&orderBy=name&search=&should_have_source=true)
+* [IntelliJ Plugin Developers Gitter](https://gitter.im/IntelliJ-Plugin-Developers/Lobby)
-* [Kotlin Reference](https://kotlinlang.org)

intro/about.md

@@ -48,7 +48,7 @@ This guide is split into several parts, similar to a text book. Each part builds
 
     Documents the API for the [Plugin Repository](https://plugins.jetbrains.com) service that JetBrains maintains and is used to host plugins. It is not necessary to know this API in order to publish plugins - plugins can be uploaded manually, or via the Gradle IntelliJ Plugin.
 
-* [**Appendix I - Resources**](/resources.md)
+* [**Appendix I - Resources**](/appendix/resources/useful_links.md)
 
     Links to useful resources, such as the IntelliJ Community Edition source code, the Plugin Development forum and the Plugin Developers Gitter room.
 

welcome.md

@@ -13,7 +13,7 @@ Welcome to the _IntelliJ Platform_ SDK. This is the primary source of documentat
     * [**Key Topics**](intro/key_topics.md)
 * [**Getting Help**](intro/getting_help.md)
 * [**Getting Started**](/basics/getting_started.md)
-* [**Resources**](resources.md)
+* [**Useful Links**](/appendix/resources/useful_links.md)
 
 ## Open Source