added nav-tabs class to jem.css

it's used for the tabs within the editevent view. As we're using the
bootstrap tabs instead of the "old" tabs the class has been added.
adapted module files

- changed versionnr
- copied language strings
- added class to type="radio"
adapted plugin-mailer

- changed versionrnr
- added class to radio type
- changed creationDate
added check for task apply to function postSaveHook

added the check to the function as it's possible to press the save +
apply button in the front and we want to trigger the mail sending in
both cases.
altered editevent view

- replaced the "old" tabs by bootstrap
removed obsolete code

- removed "old" tabs
- removed "button3" class
replaced "old" tabs by bootstrap tabs, editvenue-view
adapted function getCalendarTool, FIX #7
added Recurr to Credits
renamed language strings
removed var_Dumps
added class to type radio
adapted view-updatecheck

removed the display of changes, this as there is already a link to a
page where people can find information. Also added padding+line height
to the css for a better display
cleanup
cleanup backend
add tpl to function display
removed obsolete code
tweaked backend.css
adapted plugins
added version field to settings table