fixed link to category page in new event page
fixed problems with empty category list
added option for category sync (not implemented yet)

option to specify if the categories should be synced with the post
categories
added cat sync option in category admin page (not implemented yet)
fixed inteding in category parent combo box
implemented manual cat sync with post cats
implemented sync of categories

there are still some issues with manual and automatical sync
sync categories automatically after the option was enabled; added message for changed option
fixed category sync for categories with the same name
fixed edit_post_category

get_category provides still the old cat data in edit_category action
added check for available post data in edit_post_category
Added required comfirmation for enabling category sync
updated sync categories help text
remove categories in events when syncing with post cats
improved remove_category_in_events_function
update events when category slug was changed
update keep in sync caption
added message after manual sync; disable manual sync button if automatic sync is enabled
disable new category form, when automatic sync with post categories is enabled
fixed cat_sync option update