Show no invalid date warning when user opens upload dialogue
Show error message if no issues have been created and user clicks "next"
Show error message if no granularity has been chosen before an action
Remove caching issue with the "next" button
Improve description of date input boxes
Merge branch 'issue_217' into feature-zm_all

Conflicts:
	Goobi/src/de/sub/goobi/forms/GranularityForm.java