Update README.md: spelling of company name (#371)

Co-authored-by: Doc SoC <socadk@users.noreply.github.com>

Author: stefan-ka

README.md

@@ -117,7 +117,7 @@ That's it. You should have a clean workspace now without build errors.
 
 ## Contributing
 Contribution is always welcome! Here are some ways how you can contribute:
- * Create Github issues if you find bugs or just want to give suggestions for improvements.
+ * Create GitHub issues if you find bugs or just want to give suggestions for improvements.
  * This is an open source project: if you want to code, [create pull requests](https://help.github.com/articles/creating-a-pull-request/) from [forks of this repository](https://help.github.com/articles/fork-a-repo/). Please refer to a Github issue if you contribute this way. In our [wiki](https://github.com/ContextMapper/context-mapper-dsl/wiki/IDE-Setup) you can find out how to build the project and setup the development environment locally.
  * If you want to contribute to our documentation and user guides on our website [https://contextmapper.org/](https://contextmapper.org/), create pull requests from forks of the corresponding page repo [https://github.com/ContextMapper/contextmapper.github.io](https://github.com/ContextMapper/contextmapper.github.io) or create issues [there](https://github.com/ContextMapper/contextmapper.github.io/issues).