Update ReadMe.md

We need to slightly update the language description, according to the new communication guidelines. Additionally, we wanted to add a brief section about Kotlin Foundation here, which is now missing.

ReadMe.md

@@ -7,7 +7,7 @@
 # Kotlin Programming Language
 
 Welcome to [Kotlin](https://kotlinlang.org/)!   
-It is an open-source, statically typed programming language supported and developed by [JetBrains](https://www.jetbrains.com/) and open-source contributors.
+Kotlin is a concise multiplatform language developed by [JetBrains](https://www.jetbrains.com/) and [contributors](https://kotlinlang.org/docs/contribute.html).
 
 Some handy links:
 
@@ -23,6 +23,7 @@ Some handy links:
  * [Follow Kotlin on Twitter](https://twitter.com/kotlin)
  * [Public Slack channel](https://slack.kotlinlang.org/)
  * [TeamCity CI build](https://teamcity.jetbrains.com/project.html?tab=projectOverview&projectId=Kotlin)
+ * [Kotlin Foundation](https://kotlinfoundation.org/)
 
 ## Kotlin Multiplatform capabilities
 
@@ -154,3 +155,7 @@ Kotlin is distributed under the terms of the Apache License (Version 2.0). See [
 # Contributing
 
 Please be sure to review Kotlin's [contributing guidelines](docs/contributing.md) to learn how to help the project.
+
+# Kotlin Foundation
+
+The Kotlin Foundation is a non-profit organization whose mission is to promote and advance the Kotlin ecosystem. You can learn more about the structure and goals of the Kotlin Foundation on its [official website](https://kotlinfoundation.org/).