Added readme file to the docs directory.

Author: asbjornu

docs/readme.md

@@ -0,0 +1,40 @@
+# GitVersion Documentation
+
+This is the directory in which the
+[GitVersion documentation hosted on ReadTheDocs](http://gitversion.readthedocs.io/en/latest/)
+resides.
+
+## Contributing
+
+Improvements to the documentation is highly welcomed and is as easy
+as finding the `.md` file you want to change and editing it directly within
+GitHub's web interface.
+
+If you want to do more elaborate changes, we would appreciate if you could test
+the documentation locally before submitting a pull request. This involves
+[forking](https://guides.github.com/activities/forking/) this repository and
+then serving up the documentation locally on your machine, clicking around in
+it to ensure that everything works as expected.
+
+## Serving the documentation locally
+
+To serve up the documentation locally, you need to
+[install MkDocs](http://www.mkdocs.org/#installation) and then at the root of
+the GitVersion project write the following in a command line window:
+
+```shell
+mkdocs serve
+```
+
+After pressing enter, something similar to the following lines should appear:
+
+```
+INFO    -  Building documentation...
+INFO    -  Cleaning site directory
+[I 160810 10:48:18 server:281] Serving on http://127.0.0.1:8000
+```
+
+If it says `Serving on http://127.0.0.1:8000`, you should be able to navigate
+your favorite browser to `http://127.0.0.1:8000` and browse the documentation
+there. If you have any problems with this process, please consult the
+[MkDocs documentation](http://www.mkdocs.org/).