fix issue with next available checkin

git-svn-id: https://svn.typo3.org/TYPO3v4/Extensions/ab_booking/trunk@84004 735d13b6-9817-0410-8766-e36946ffe9aa
saved changes to myfullcalendar.js

git-svn-id: https://svn.typo3.org/TYPO3v4/Extensions/ab_booking/trunk@84007 735d13b6-9817-0410-8766-e36946ffe9aa