Add GitHub Action's linter to check markdown files and remove invalid…

… links

When a pr is opened the linter will run over all md files and check if a link is not valid.

# Notes:
- Some md files were removed because I couldn't file a redirection to them:
  - deleted:    coverpage.md
  - deleted:    developer-guides/android-developer-guide.md
  - deleted:    developer-guides/samples.md
  - deleted:    ../start/coverpage.md
- The removed link were removed from the doc, it doesn't makes sense have an invalid link.
For example:
  - https://www.ekito.fr/people/sparkjava-and-koin/
  - https://medium.com/mindorks/using-dependency-injection-with-koin-bee0b461714a
- Config Files comments:
  - CHANGELOG.md is excluded from the linter.
  It contains a lot of github links, so when the linter checks it, GitHub returns a max requests reached error (429 HTTP error code).
  The [linter library is adding a feature to fix this case. However, they have to release a new version with this feature](tcort/markdown-link-check#114).
  - https://developer.android.com/ links are removed from the check because it requires authentication, so they fail due to an redirect loop.

.config/mlc_config.json

@@ -0,0 +1,7 @@
+{
+  "ignorePatterns": [
+    {
+      "pattern": "^https://developer.android.com"
+    }
+  ]
+}

.github/workflows/check_md.yml

@@ -0,0 +1,16 @@
+name: Check Markdown links
+on: pull_request
+jobs:
+  markdown-link-check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@master
+      - uses: gaurav-nelson/github-action-markdown-link-check@v1
+        with:
+          use-verbose-mode: 'yes'
+          config-file: '.config/mlc_config.json'
+          # CHANGELOG.md is excluded.
+          # GitHub returns 429 error code due to the amount of requests.
+          # This will be fixed after https://github.com/tcort/markdown-link-check/issues/114 be released
+          folder-path: 'koin-projects, .github'
+          file-path: './README.md, ./CODE_OF_CONDUCT.md'

.gitignore

@@ -8,5 +8,3 @@ classes/
 .DS_Store
 /build
 /captures
-
-

README.md

@@ -187,7 +187,7 @@ class MyApplication : Application() {
 ### Articles
 
 * [Dagger is dead. Long live Koin](https://www.linkedin.com/pulse/dagger-dead-long-live-koin-yordan-olave-cordero)
-* [Testing a Koin application with KotlinTest](https://dev.to/kerooker/testing-koin-applications-with-kotlintest-1iip)
+* [Testing a Koin application with KotlinTest](https://medium.com/@mutebibrian256/testing-koin-applications-with-kotlintest-d2ff9b23fff4)
 * [Ready for Koin 2.0](https://medium.com/koin-developers/ready-for-koin-2-0-2722ab59cac3)
 * [Migration from Dagger2 to Koin](https://proandroiddev.com/migrating-from-dagger2-to-koin-3b2b3f5285e9)
 * [From Dagger to Koin, a step by step migration guide](https://medium.com/@giuliani.arnaud/the-thermosiphon-app-from-dagger-to-koin-step-by-step-a09af7f5b5b1)
@@ -197,8 +197,6 @@ class MyApplication : Application() {
 * [Testing with Koin](https://proandroiddev.com/testing-with-koin-ade8a46eb4d)
 * [Painless Android testing with Room & Koin](https://android.jlelse.eu/painless-android-testing-with-room-koin-bb949eefcbee)
 * [Unlock your Android ViewModel power with Koin](https://medium.com/@giuliani.arnaud/unlock-your-android-viewmodel-power-with-koin-23eda8f493be)
-* [Using dependency injection with Koin](https://medium.com/mindorks/using-dependency-injection-with-koin-bee0b461714a)
-* [Koin + Spark = ❤️]()
 * [Push SparkJava to the next level](https://medium.com/koin-developers/pushing-sparkjava-to-the-next-level-with-koin-ed1f0b80953e) ([Kotlin Weekly issue 73](http://mailchi.mp/kotlinweekly/kotlin-weekly-73), [DZone.com](https://dzone.com/articles/push-sparkjava-to-the-next-level-with-koin) )
 * [When Koin met Ktor ...](https://medium.com/koin-developers/when-koin-met-ktor-c3b2395662bf) ([Kotlin Weekly issue 72](https://us12.campaign-archive.com/?u=f39692e245b94f7fb693b6d82&id=3135ae0cf5))
 * [Android Dependency Injection – Why we moved from Dagger 2 to Koin?](https://www.nan-labs.com/blog/android-dependency-injection-moved-dagger-2-koin/)

koin-projects/docs/reference/sidebar.md

@@ -1,33 +1,33 @@
-- [Intro](introduction)
-- [Setup](setup/index)
-- [Koin MP - Alpha](setup/koin_mp)
+- [Intro](./introduction.md)
+- [Setup](./setup/index.md)
+- [Koin MP - Alpha](./setup/koin_mp.md)
 - **Koin Core**
-- [Koin DSL](koin-core/dsl)
-- [Definitions](koin-core/definitions)
-- [Modules](koin-core/modules)
-- [Start Koin](koin-core/start-koin)
-- [Koin Component](koin-core/koin-component)
-- [Injecting Parameters](koin-core/injection-parameters)
-- [Setters Injection](koin-core/setters)
-- [Scope API](koin-core/scopes)
-- [Using Java](koin-core/java)
-- [Logging](koin-core/logging)
-- [Properties](koin-core/properties)
-- [Experimental Features](koin-core/experimental)
+- [Koin DSL](./koin-core/dsl.md)
+- [Definitions](./koin-core/definitions.md)
+- [Modules](./koin-core/modules.md)
+- [Start Koin](./koin-core/start-koin.md)
+- [Koin Component](./koin-core/koin-component.md)
+- [Injecting Parameters](./koin-core/injection-parameters.md)
+- [Setters Injection](./koin-core/setters.md)
+- [Scope API](./koin-core/scopes.md)
+- [Using Java](./koin-core/java.md)
+- [Logging](./koin-core/logging.md)
+- [Properties](./koin-core/properties.md)
+- [Experimental Features](./koin-core/experimental.md)
 - **Koin Test**
-- [JUnit & Mocks](koin-test/testing)
-- [CheckModules gradle Plugin](koin-test/checkmodules_plugin)
+- [JUnit & Mocks](./koin-test/testing.md)
+- [CheckModules gradle Plugin](./koin-test/checkmodules_plugin.md)
 - **Koin Android**
-- [Start on Android](koin-android/start)
-- [Android DSL](koin-android/dsl)
-- [Retrieve Instances](koin-android/get-instances)
-- [Koin Scope](koin-android/scope)
-- [ViewModel](koin-android/viewmodel)
-- [Fragment Factory](koin-android/fragment-factory)
-- [Work Manager](koin-android/workmanager)
-- [Compose](koin-android/compose)
+- [Start on Android](./koin-android/start.md)
+- [Android DSL](./koin-android/dsl.md)
+- [Retrieve Instances](./koin-android/get-instances.md)
+- [Koin Scope](./koin-android/scope.md)
+- [ViewModel](./koin-android/viewmodel.md)
+- [Fragment Factory](./koin-android/fragment-factory.md)
+- [Work Manager](./koin-android/workmanager.md)
+- [Compose](./koin-android/compose.md)
 - **Koin Ktor**
-- [Injecting with Ktor](koin-ktor/ktor)
+- [Injecting with Ktor](./koin-ktor/ktor.md)
 - **Links**
 - [Changelog](https://github.com/InsertKoinIO/koin/blob/master/CHANGELOG.md)
 - [WebSite](https://insert-koin.io/)