Fix agenda csv export to show full time

Fix agenda csv export to show full time

Max Mustermann writes:

> Org-mode version 6.21b in GNU Emacs 23.1.1 (i486-pc-linux-gnu, GTK+
> Version 2.18.3) of 2009-11-10 on vernadsky, modified by Debian.
>
> The Org entry:
>
>   * Appointments 			       :work:
>   #+CATEGORY: Appt
>   ** Testing <2010-02-20 Sat 22:00-23:30>
>
> produces the following incomplete output with org-batch-agenda-csv :
>
>   emacs -batch -l ~/.emacs -eval '(org-batch-agenda-csv "a"
> org-agenda-ndays 1)'
>   Appt,Testing,timestamp,,work,2010-2-20,2200,,,1000,2010-2-20
>
> whereas the output of org-batch-agenda shows the correct time:
>
>   emacs -batch -l ~/.emacs -eval '(org-batch-agenda "a" org-agenda-ndays 1)'
>   Appt:       22:00-23:30 Testing                  :work::