Disable secure/insecure http change for WebDAV collection sources
When the properties dialog of a Webdav-addressbook/taks list/calendar/memo list, contained within a collection account, is shown, the WebDAV-URL is displayed to the user and the user cannot change it. But the user can switch the TLS on and off.
- Change the Properties dialog for collection URLS within collection accounts, so that the user cannot switch from secure to insecure connection.