fix editevent select venue / contact (issue #655)

- respect entry limit
- correct url on navigation buttons
not fixed yet: on navigation sorting gets lost
Update editevent.php

fixed a bug I made in _buildContactOrderBy()
more fix editevent select venue / contact (issues #655, #667)

- hopefully all working on these two popups
- show "No ... found." when table empty
- removed email, address, phone from contacts list (#667)
- removed "Powered by" from popups, added to all other views (e.g. calendars, edit views)
Merge pull request #668 from Hoffi1/develop

fix frontend editevent popups, privacy (issues #655, #667)