Merge branch '99-trim-instance-access-codes' into 'develop'

Resolve "Trim access codes on instance creation"

See merge request !107

src/main/java/cz/muni/ics/kypo/training/adaptive/service/training/TrainingInstanceService.java

@@ -115,7 +115,7 @@ public class TrainingInstanceService {
      * @return created {@link TrainingInstance}
      */
     public TrainingInstance create(TrainingInstance trainingInstance) {
-        trainingInstance.setAccessToken(generateAccessToken(trainingInstance.getAccessToken()));
+        trainingInstance.setAccessToken(generateAccessToken(trainingInstance.getAccessToken().trim()));
         if (trainingInstance.getStartTime().isAfter(trainingInstance.getEndTime())) {
             throw new EntityConflictException(new EntityErrorDetail(TrainingInstance.class, "id", trainingInstance.getId().getClass(), trainingInstance.getId(),
                     "End time must be later than start time."));