[sync] SyncML improvements

[Martin Middeke]

Hi again...

> I also tried the sync with kronolith now. seems to work great. no
> problems for now - the only thing is that my old "entries" kill the
> phone app - with a complete fresh calendar everything works fine...
> maybe some field-match problems i think, but unfortunately i cannot tell
>  you anything to that :/
now i can say:
event sync only get in trouble with events:

1) a member is set
2) a recurrence is set

that is what i can tell for now!

cu list
Martin