Make the link to issue template bold

Makes it easier to see the issue template link. And hopefully more we don't have to tell everybody that much that they should use it.

CONTRIBUTING.md

@@ -4,7 +4,7 @@ If you have questions about how to install or use ownCloud, please direct these
 
 ### TL;DR
 
- * The [issue template can be found here][template] but be aware of the different repositories! See list below.
+ * The [**issue template can be found here**][template] but be aware of the different repositories! See list below.
 
 ### Guidelines
 * Please search the existing issues first, it's likely that your issue was already reported or even fixed.