sick note, added fields aubStartDate + aubEndDate

* adjusted sick note form
* adjusted sick note list and detail view

refs #9469
sick note form, added validation for AU period

refs #9469
sick note form, usability (js)

* show AU period fields only if AU present radiobutton clicked on 'yes'
* if AU present radiobutton clicked on 'no' hide AU period fields

refs #9469
adjusted tablesorter functionality

* added parser for germandate
* added parser for digits with comma
* sick note list and application list now sortable

refs #9469