r11511: A classic "friday night check-in" :-). This moves much

r11511: A classic "friday night check-in" :-). This moves much
of the Samba4 timezone handling code back into Samba3.
Gets rid of "kludge-gmt" and removes the effectiveness
of the parameter "time offset" (I can add this back
in very easily if needed) - it's no longer being
looked at. I'm hoping this will fix the problems people
have been having with DST transitions. I'll start comprehensive
testing tomorrow, but for now all modifications are done.
Splits time get/set functions into srv_XXX and cli_XXX
as they need to look at different timezone offsets.
Get rid of much of the "efficiency" cruft that was
added to Samba back in the day when the C library
timezone handling functions were slow.
Jeremy.