Merge pull request #3700 from ornladios/vicentebolea-patch-2

Update Readme.md with community section

ReadMe.md

@@ -74,6 +74,14 @@ Once ADIOS2 is installed refer to:
 
 * Previous releases: [https://github.com/ornladios/ADIOS2/releases](https://github.com/ornladios/ADIOS2/releases)
 
+## Community
+
+ADIOS2 is an open source project: Questions, discussion, and contributions are welcome. Join us at:
+
+- Slack workspace: [![Slack](https://img.shields.io/badge/slack-ADIOS2-pink.svg)](https://adios2.spack.io) 
+- Mailing list: adios-ecp@kitware.com 
+- Github Discussions: https://github.com/ornladios/ADIOS2/discussions
+
 ## Reporting Bugs
 
 If you find a bug, please open an [issue on ADIOS2 github repository](https://github.com/ornladios/ADIOS2/issues)
@@ -86,8 +94,8 @@ See the [Contributor's Guide to ADIOS 2](Contributing.md) for instructions on ho
 ADIOS2 is licensed under the Apache License v2.0.
 See the accompanying [Copyright.txt](Copyright.txt) for more details.
 
-
 ## Directory layout
+
 * bindings - public application programming interface, API, language bindings (C++11, C, Fortran, Python and Matlab)
 
 * cmake - Project specific CMake modules