Added license to README and mentioned OGS community.

README.md

 # OpenGeoSys 6 #
 
-## Intro ##
+***This is the source code of the next generation [OpenGeoSys][ogs].***
 
-***This is the source code of the next generation [OpenGeoSys](http://www.opengeosys.net).***
-
-At the moment we are evaluating Git and Github as our main development infrastructure.
-To get started with Github have a look at these [customized help pages](http://ufz.github.com/help) or at
-[these slides](https://svn.ufz.de/ogs/raw-attachment/wiki/ogs6plan/Collaborative%20development%20with%20Git%20and%20Github%2C%20Lars%20Bilke.pdf). 
-
-## OpenGeoSys ##
+## The OpenGeoSys-project ##
 
 OpenGeoSys (OGS) is a scientific open source project for the development of
 numerical methods for the simulation of thermo-hydro-mechanical-chemical
@@ -17,10 +11,24 @@ is object-oriented with an focus on the numerical solution of coupled multi-fiel
 problems (multi-physics). Parallel versions of OGS are available relying on
 both MPI and OpenMP concepts. Application areas of OGS are currently CO2
 sequestration, geothermal energy, water resources management, hydrology and 
-waste deposition.
+waste deposition. OGS is comprised of the THMC-simulator (simply referred to as
+*"OGS"*) and a visualization tool (*"Data Explorer"*). OGS is developed by the
+[OpenGeoSys Community][ogs].
+
+## Software development ##
+
+- To get started checkout the [developer guide][devguide]
+- For the actual build status see the [Jenkins-CI server][jenkins-ci]
+- Have a look at the [Doxygen documentation][docs]
+
+## License ##
 
-## Development ##
+OpenGeoSys is distributed under a Modified BSD License which encourages users to
+attribute the work of the OpenGeoSys Community especially in scientific
+publications. See the [LICENSE.txt][license-source] for the license text.
 
-- To get started checkout the [developer guide](http://ufz.github.com/devguide)
-- For the actual build status see the [Jenkins-CI server](https://svn.ufz.de/hudson/view/OGS-6/)
-- Have a look at the [Doxygen documentation](https://svn.ufz.de/hudson/view/OGS-6/job/OGS-6-Docs/lastSuccessfulBuild/artifact/build/docs/index.html)
\ No newline at end of file
+[ogs]: http://www.opengeosys.net
+[devguide]: http://ufz.github.com/devguide
+[jenkins-ci]: https://svn.ufz.de/hudson/view/OGS-6/
+[docs]: https://svn.ufz.de/hudson/view/OGS-6/job/OGS-6-Docs/lastSuccessfulBuild/artifact/build/docs/index.html
+[license-source]: https://github.com/ufz/ogs/blob/license/LICENSE.txt