Added javadocs to exceptions.

src/main/java/ch/zhaw/pm2/racetrack/InvalidFileFormatException.java

@@ -1,5 +1,8 @@
 package ch.zhaw.pm2.racetrack;
 
+/**
+ * Class for Exception when invalid Fileformat is used.
+ */
 public class InvalidFileFormatException extends Exception {
     public InvalidFileFormatException(String errorMessage) {
         super(errorMessage);

src/main/java/ch/zhaw/pm2/racetrack/InvalidTrackFormatException.java

@@ -1,5 +1,8 @@
 package ch.zhaw.pm2.racetrack;
 
+/**
+ * Class for Exception when invalid track format is used.
+ */
 public class InvalidTrackFormatException extends Exception {
     public InvalidTrackFormatException(String errorMessage) {
         super(errorMessage);