Fix text scaling issues

Status bar clock text and the text in the launcher tab labels had ugly
jagged edges. This happened when using small font sizes and drawing
the text directly using QPainter::drawText(). Fixed by drawing the
texts to offscreen pixmaps first and then drawing those pixmaps.

Open-webOS-DCO-1.0-Signed-off-by: Teppo Pennanen <teppo.pennanen@palm.com>

Change-Id: Ifac7e0a09cd1c9f9853847291d728f4cd27fb2d1