fixed css issue in filterbar hlist when list-style-image is used
some html output code style fixes
added option to change dateformat in event new/edit form
complete rewrite of date handling in new/edit event form and validating the given data

For date validation only the standard SQL date format e.g. 2014-01-31
will be used. For displaying another date format can be used, but this
data will not be used directly.
moved admin settings page styles to css file; fixed some style issues
preparation for version 0.6.2
Merge branch 'develop'
fixed event-list.css url (removing double slash)
only load event-list styles on frontpage only if required
fixed date check for PHP version 5.2
whitespace fix
fixed problem that after adding a new event the new event wasn't edited

There was an issue that after adding a new event the copy of the event
was shown. The correct behavior would be to give the possibility to edit
the new event. But instead a new event would be created if "Publish" was
clicked.
some whitespace fixes
stripslashes in event time before writing to db
modifications in truncate function

changed and added new parameters
added and implemented options to allow html tags in time and location
fixed truncate in admin event table

required due to change of truncate function
escape event time html in admin event table
fixed bug in changed truncate function
replaced "..." with html entity "&hellip;"