Merge pull request #662 from edizor/master

Update README

Author: lor6

core-kotlin-modules/core-kotlin-advanced-2/README.md

@@ -12,3 +12,4 @@ This module contains articles about advanced topics in Kotlin.
 - [Kotlin Generic Inline Classes](https://www.baeldung.com/kotlin/generic-inline-classes)
 - [Callback Functions in Kotlin](https://www.baeldung.com/kotlin/callback-functions)
 - [Resolving Kotlin Error: ‘public’ function exposes its ‘public/*package*/’ return type](https://www.baeldung.com/kotlin/public-function-exposes-its-public-package-return-type)
+- [Functional Error Handling in Kotlin](https://www.baeldung.com/kotlin/functional-error-handling)

core-kotlin-modules/core-kotlin-arrays-2/README.md

@@ -1,2 +1,3 @@
 ## Relevant Articles
 - [Get Subarray of an Array Between Given Positions in Kotlin](https://www.baeldung.com/kotlin/subarray-index-range)
+- [Removing the First Element From an Array in Kotlin](https://www.baeldung.com/kotlin/array-remove-first-element)

core-kotlin-modules/core-kotlin-collections-list/README.md

@@ -8,3 +8,5 @@ This module contains articles about core Kotlin collections.
 - [Converting a Custom Object List to Simple List in Kotlin](https://www.baeldung.com/kotlin/list-custom-object-simple-conversion)
 - [Convert Map to List in Kotlin](https://www.baeldung.com/kotlin/map-list-transformation)
 - [Swap Elements in MutableList in Kotlin](https://www.baeldung.com/kotlin/mutablelist-swap-items)
+- [Removing the First Element From an ArrayList in Kotlin](https://www.baeldung.com/kotlin/arraylist-delete-first-element)
+- [Apply a Function to Each Element of a List in Kotlin](https://www.baeldung.com/kotlin/list-apply-function-to-each-item)

core-kotlin-modules/core-kotlin-datastructures/README.md

@@ -14,3 +14,4 @@ This module contains articles about data structures in Kotlin
 - [Merge Sort in Kotlin](https://www.baeldung.com/kotlin/merge-sort)
 - [How to Sort Elements in Lexicographical Order in Kotlin](https://www.baeldung.com/kotlin/lexicographical-sort)
 - [Matrix Addition and Multiplication in Kotlin](https://www.baeldung.com/kotlin/matrix-addition-multiplication)
+- [Insert an Element at a Given Position Into an Array in Kotlin](https://www.baeldung.com/kotlin/array-insert-item-chosen-index)

kotlin-testing/README.md

@@ -9,3 +9,4 @@ This module contains articles about testing in Kotlin
 - [MockK: A Mocking Library for Kotlin](https://www.baeldung.com/kotlin/mockk)
 - [Testing a Lambda Function With Mockito Kotlin](https://www.baeldung.com/kotlin/mockito-verify-lambda)
 - [How to Mock and Verify Lambda Expression in Kotlin](https://www.baeldung.com/kotlin/lambda-mock-verify)
+- [Testing Extension Methods in Kotlin](https://www.baeldung.com/kotlin/test-extension-methods)