Merge pull request #3156 from kunaltyagi/readme-updates

Update README.md with new information

CONTRIBUTING.md

@@ -16,8 +16,17 @@ the preferred channel for submitting [pull requests](#pull-requests) and
 [bug reports](#bugs), but please respect the following
 restrictions:
 
-* Please **do not** use the issue tracker for personal support requests (use
-  [mailing list](http://www.pcl-users.org/)).
+* Please **do not** use the issue tracker for personal support requests. Please
+  consider one of the following alternatives instead:
+  * [Stack Overflow](https://stackoverflow.com/questions/tagged/point-cloud-library)
+  for Q&A as well as support for troubleshooting, installation and debugging. Do
+  remember to tag your questions with the tag `point-cloud-library`.
+  * [Gitter channel](https://gitter.im/PointCloudLibrary/pcl) for live chat with
+  other members of the PCL community and casual discussions
+
+<!-- 
+  * Mailing list: The [PCL Google Group](https://groups.google.com/forum/#!forum/point-cloud-library)
+-->
 
 * Please **do not** derail or troll issues. Keep the discussion on topic and
   respect the opinions of others.

README.md

@@ -14,16 +14,28 @@
 Continuous integration
 ----------------------
 
-Ubuntu | Windows | MacOS
------- | ------- | -----
-[![Ubuntu Build Status][ci-ubuntu-image]][ci-ubuntu] | [![Windows Build Status][ci-windows-image]][ci-windows] | [![MacOS Build Status][ci-macos-image]][ci-macos]
+[![Ubuntu Build Status][ci-ubuntu-image]][ci-ubuntu] [![Windows Build Status][ci-windows-image]][ci-windows] [![MacOS Build Status][ci-macos-image]][ci-macos]
 
 [ci-ubuntu]: https://dev.azure.com/PointCloudLibrary/pcl/_build/latest?definitionId=4
-[ci-ubuntu-image]: https://dev.azure.com/PointCloudLibrary/pcl/_apis/build/status/Build.Ubuntu
+[ci-ubuntu-image]: https://img.shields.io/azure-devops/build/PointCloudLibrary/0fc52e87-00b9-420e-acbc-c842c4f2d9cc/4.svg?label=Ubuntu&logo=azure%20pipelines
 [ci-windows]: https://dev.azure.com/PointCloudLibrary/pcl/_build/latest?definitionId=3
-[ci-windows-image]: https://dev.azure.com/PointCloudLibrary/pcl/_apis/build/status/Build.Windows
+[ci-windows-image]: https://img.shields.io/azure-devops/build/PointCloudLibrary/0fc52e87-00b9-420e-acbc-c842c4f2d9cc/3.svg?label=Windows&logo=azure%20pipelines
 [ci-macos]: https://dev.azure.com/PointCloudLibrary/pcl/_build/latest?definitionId=2
-[ci-macos-image]: https://dev.azure.com/PointCloudLibrary/pcl/_apis/build/status/Build.MacOS
+[ci-macos-image]: https://img.shields.io/azure-devops/build/PointCloudLibrary/0fc52e87-00b9-420e-acbc-c842c4f2d9cc/2.svg?label=MacOS&logo=azure%20pipelines
+
+Community
+---------
+[![Gitter][gitter-image]][gitter-channel]
+[![StackOverflow][so-question-count]][stackoverflow]
+[![Website][website-status]][website]
+
+[gitter-image]: https://img.shields.io/gitter/room/PointCloudLibrary/pcl.svg?label=community%20chat&logo=gitter&logoColor=%23ED1965
+[gitter-channel]: https://gitter.im/PointCloudLibrary/pcl
+[website-status]: https://img.shields.io/website/http/www.pointclouds.org.svg?down_color=red&down_message=is%20down&up_color=yellow&up_message=is%20outdated
+[website]: http://www.pointclouds.org
+
+[so-question-count]: https://img.shields.io/stackexchange/stackoverflow/t/point-cloud-library.svg?logo=stackoverflow
+[stackoverflow]: https://stackoverflow.com/questions/tagged/point-cloud-library
 
 Description
 -----------
@@ -49,9 +61,22 @@ Please read [CONTRIBUTING.md](https://github.com/PointCloudLibrary/pcl/blob/mast
 
 Issues
 ------
-For general questions on how to use the PCL, please use the [pcl-users](http://www.pcl-users.org/) mailing list (do not forget to subscribe before posting).
 To report issues, please read [CONTRIBUTING.md#bug-reports](https://github.com/PointCloudLibrary/pcl/blob/master/CONTRIBUTING.md#bug-reports).
 
+For general questions on how to use the PCL, please consider one of the following alternatives instead:
+* [Stack Overflow](https://stackoverflow.com/questions/tagged/point-cloud-library)
+for Q&A as well as support for troubleshooting, installation and debugging. Do
+remember to tag your questions with the tag `point-cloud-library`.
+* [Gitter channel](https://gitter.im/PointCloudLibrary/pcl) for live chat with
+other members of the PCL community and casual discussions
+
+<!-- 
+  * Mailing list: The [PCL Google Group](https://groups.google.com/forum/#!forum/point-cloud-library)
+-->
+
+<!-- There's an option of creating our own compatibility tracker
+
 API/ABI Compatibility Report
 ------
 For details about API/ABI changes over the timeline please check PCL's page at [ABI Laboratory](https://abi-laboratory.pro/tracker/timeline/pcl/).
+-->