Apply feature detection profile to feed APIs (bug 1103169)
Merge pull request #828 from diox/filter-feed-by-features-too

Apply feature detection profile to feed APIs (bug 1103169)
remove extra top margin on feed app preview tiles (bug 1109232)
Merge pull request #839 from ngokevin/prevmargin

remove extra top margin on feed app preview tiles (bug 1109232)
Persist user settings between refresh (bug 1107484)
fix package zipping
add smooth scrolling to mobile nav; simplify mobile nav offsets (bug 1109260, bug 1059002)