implement pexecute_first to PDO database class to return a result right away

Signed-off-by: Michael Kaufmann (d00p) <d00p@froxlor.org>
change pexecute tp pexecute_first in phpinterface-classes

Signed-off-by: Michael Kaufmann (d00p) <d00p@froxlor.org>
migrate ticket-system to PDO database class, refs #1287

Signed-off-by: Michael Kaufmann (d00p) <d00p@froxlor.org>
more fixes for migration to PDO, refs #1287

Signed-off-by: Michael Kaufmann (d00p) <d00p@froxlor.org>