fixed possible issue with url casing in discovery
changed resolveURL to return false in case of failure

previously it returned the original URL in lower case which
broke communication with servers that care for the case.
0.2.5
fixed possible issue with deleting multiple calendars/addressbooks
fixed issue with folder uris on some servers.
added workaround for wrong URIs returned by SOGo server
0.2.6
fixed error display in mojo-validator
added url scheme for SOGo server.
reworked url resolving to reduce case manipulation as much as possible