Rework the bookmark app to manage postgresql.
Add a fetchOne function into the PdoStmtWrapper
Fix a tipo in comments.

 * a notice would be reported if either of the 'cal' or 'event' $_GET params
   where not supplied, which would result in 'Cannot modify header information'
   warnings

 * the description field was removed in commit:
     f3f5d775
   but the field was still trying to be mapped - causing errors with CalDAV

This is not needed anymore since commit
6b64aa3f.

Signed-off-by: Florian Pritz <bluewind@xinu.at>

This solves a problem where hitting a redirect page would lead to a "302
Found" title.

Signed-off-by: Florian Pritz <bluewind@xinu.at>

Reverting as per Georg's request (not stable enough yet)

This reverts commit 55ab68a3.