[de] Fix some incorrect comment syntax in german translation

- This makes it easier to use tools for automatic merge of original english
   text to german translation
[de] Chapter 2: Merge original english updates to german translation and translate them
[de] Chapter 3: Merge original english updates to german translation and translate them
[de] Chapter 4: Merge original english updates to german translation and translate them
[de] Chapter 5: Merge original english updates to german translation and translate them
[de] Chapter 6: Merge original english updates to german translation
[de] Chapter 7: Merge original english updates to german translation and translate them
[de] Chapter 8: Merge original english updates to german translation
[de] Chapter 9: Merge original english updates to german translation
Merge pull request #627 from progit-de/next

Merge changes from english translation to german translation