Fix issues reported by intellij inspect code

[TimvdLippe]

Fixed various issues that were reported by IntelliJ inspect code on master.

Steps to reproduce on current master

1. Right click the project jpacman-framework
2. Click Analyze
3. Click Inspect code...
4. After the inspection is done, observe a new tab Inspection with the corresponding warnings

   Issues that were fixed:

   • Collapsed an XML statement
   • Changed for-loop to foreach loop
   • Simplified if-statement
   • Simplified generic arguments of maps. They can be inferred by the left-hand side declaration
   • Fixed Javadoc invalid reference to the getGame method