Merge pull request #1428 from rcalago/master

Update on README.md

Author: lor6

scala-core-collections-modules/scala-core-collections-4/README.md

@@ -1,2 +1,3 @@
 ## Relevant Articles
 - [Using filter() and takeWhile() With Collections in Scala](https://www.baeldung.com/scala/filter-takewhile)
+- [Finding Elements in a List using takeWhile() and dropWhile() in Scala](https://www.baeldung.com/scala/list-find-takewhile-dropwhile)

scala-core-modules/scala-core-9/README.md

@@ -6,3 +6,4 @@
 - [Find Two’s Complement of a Number in Scala](https://www.baeldung.com/scala/compute-twos-complement)
 - [Convert Option to Either in Scala](https://www.baeldung.com/scala/option-either-conversion)
 - [Meaning of _root_ In Scala Import Clause](https://www.baeldung.com/scala/root-import-clause)
+- [Check if All Characters in a Scala String Are Either Upper or Lower Case](https://www.baeldung.com/scala/string-check-all-characters-upper-lower-case)

scala-core-modules/scala-core-fp/src/main/scala/com/baeldung/scala/freemonad/README.md

@@ -0,0 +1,2 @@
+### Relevant Articles
+- [Free Monads in Scala](https://www.baeldung.com/scala/free-monads)

scala-sbt/README.md

@@ -4,3 +4,4 @@
 - [Setting up Global Configurations in SBT](https://www.baeldung.com/scala/sbt-global-configurations)
 - [Safer Scala Code by Using WartRemover](https://www.baeldung.com/scala/wartremover)
 - [Integration Testing with SBT](https://www.baeldung.com/scala/sbt-integration-testing)
+- [Introduction to Scalafix](https://www.baeldung.com/scala/scalafix)