tweak utility/zoom main content css
add some shadows, move 2 prefs-related classes to prefs.css
fix headlines-frame border color
apply heading style to h4
fix some feedtree wobbling caused by expandoicon (wtf), do not use semibold font on feedtree
do not use semibold fonts on main toolbar
minor fixes for toolbar wobbling
remove some unused shadows
increase main reading font to 15px and set line-height to 1.5
Merge remote-tracking branch 'upstream/master'