rework accelerated pan logic to avoid assert and extra calculations
use xz compression for deb packages (if cpack supports it)
do not rebuild the toolbar here.  It causes the toolbar to get rebuilt too early
on some window managers and the toolbar is forever hidden and opencpn unusable,
if any plugin installs a toolbar icon. The toolbar is already rebuilt at startup
and after options so doing so here is not needed.
fix compression setup logic to avoid crash
fix bad rendering problems for opengles
update grib plugin to not use gldrawpixels.  This is faster and works on opengles