MainFrm: delay setting video output rect

Should fix all remaining visual glitches that appear while opening new
videos
MainFrm: fix auto-zoom for negative working areas

For example on displays positioned on the left side of the main one,
mpc-hc window tended to crawl to the right.
MainFrm: initialize status time immediately
MainFrm: respect minimum allowed sizes of panels
Include auto-hidden toolbar in OnGetMinMaxInfo()