remove .md file endings in links

_index.md

@@ -7,10 +7,10 @@ Welcome to card10 Wiki. You can [browse](https://git.card10.badge.events.ccc.de/
 
 **card10** is the name of the badge for the 2019 [Chaos Communication Camp](https://events.ccc.de/camp/2019/wiki/Main_Page). 
 
-### [Getting started](/en/gettingstarted.md) 
+### [Getting started](/en/gettingstarted) 
 First steps with your card10
 
-### [tl;dr](/en/tldr.md)
+### [tl;dr](/en/tldr)
 Spare me the details just give me the links to the docs!
 
 ## Overview