Add phpugms-logo to readme and website

Author: bcremer

README.md

@@ -1,5 +1,7 @@
 # PHP Usergroup Münster
 
+<img src="assets/phpugms-logo.svg" width="200">
+
 * Find upcoming meetups on [Meetup](https://www.meetup.com/phpugms/)
 * Follow us on [Twitter](https://twitter.com/phpugms/)
 * Contribute Slides and links on [GitHub](https://github.com/phpugms/)