add author to styleguide

docs/styleguide.md

@@ -41,5 +41,5 @@ See [here](styleguide/v1/Icon-Samples.pdf) for some examples. There are more in
 ## Licenses
 
 All used fonts are licensed under the [SIL Open Font License](styleguide/v1/Fonts/License-OFL.txt).
-All other parts of the design are licensed as [CC-BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/legalcode) [(human readable version)](https://creativecommons.org/licenses/by-sa/4.0/).
+All other parts of the design are licensed as [CC-BY-SA 4.0](https://creativecommons.org/licenses/by-sa/4.0/legalcode) [(human readable version)](https://creativecommons.org/licenses/by-sa/4.0/) and created by [Veith Yäger](https://veith-yaeger.de).