Datetick with zooming panning and subplots

Date formatted tick labels, automatically updated when zoomed or panned. Arguments are identical to those of DATETICK. Allows 2 or more subplots, keeps all of them synched using LINKPROP.

For best results with multiple subplots, call datetick2 from the axis that has the widest range of dates. This functionality could be included, but would probably needlessly bloat the code.

Example:
figure
h(1)=subplot(411);
plot(now:1:now+100,randn(101,1))
h(2)=subplot(412);
plot(now:1:now+10,rand(11,1))
h(3)=subplot(413);
plot(now+20:1:now+30,rand(11,1))
h(4)=subplot(414);
plot(now-5:1:now+5,rand(11,1))
datetick2