Crossport r980672 by winterz from trunk to the enterprise4 branch:

write VTIMEZONE components for scheduling calendars and other situations when
a calendar is created from in-memory incidences.

CCBUG: 177002
MERGE: e4 (e35 also, if the libical there supports VTIMEZONES.. can't remember if it does)

svn path=/branches/kdepim/enterprise4/kdepimlibs/; revision=980928