fix dates on coaches page

Author: lislis

coach.md

@@ -14,7 +14,7 @@ There will be a coaching and awareness training before the workshop.
 
 ### Important information
 - **Coaches Training:** Thursday, September 28, 2017
-- **Workshop:** October 7 and 8, 2017 (Friday evening and Saturday)
+- **Workshop:** October 6 and 7, 2017 (Friday evening and Saturday)
 - **Location:** Berlin, [Wooga office](https://www.google.de/maps/place/Wooga/@52.5293528,13.4092054,13.3z/data=!4m5!3m4!1s0x0:0x69f3e8333126bae7!8m2!3d52.5287037!4d13.4161895)
 - Please sign up in advance, link below!