Added the community section to the README.md

Signed-off-by: Dmitriy Pavlenko <dmitriy.pavlenko@sysgears.com>

README.md

@@ -1,11 +1,20 @@
 Grain
 =====
 
-Grain is a lightweight and yet powerful static website generator for [Groovy][Groovy] which purpose is
+Grain is a lightweight and yet powerful static website generator for [Groovy][] which purpose is
 to make demanding site implementation intuitive and enjoyable. Grain framework is equally well-suited
 for any static website, whether it is a complex company site or a neat blog. The framework applies
 simple website building concepts and allows to develop rapidly by making and seeing changes on the fly.
 
+Grain Community
+===============
+
+There are many ways of getting involved:
+
+- [Mailing List][] - reach us or ask the community for help
+- [Issue Tracker][] - make Grain better by suggesting improvements
+- [Twitter][] - keep up with the latest Grain news and announcements
+
 Getting Started
 ===============
 
@@ -97,9 +106,12 @@ certifies the following:
 License
 =======
 
-Grain is licensed under the terms of the [Apache License, Version 2.0][Apache License, Version 2.0].
+Grain is licensed under the terms of the [Apache License, Version 2.0][].
 
 [Grain]: http://sysgears.com/grain/
 [Groovy]: http://groovy.codehaus.org/
 [Apache License, Version 2.0]: http://www.apache.org/licenses/LICENSE-2.0.html
 [Developer Certificate of Origin]: https://raw.github.com/sysgears/grain/master/DCO
+[Mailing List]: https://groups.google.com/forum/#!forum/grain-user
+[Issue Tracker]: https://github.com/sysgears/grain/issues
+[Twitter]: http://twitter.com/grainframework