FIX: Broken build
FIX: Bug when sorting by category column, navigating to home
FEATURE: auto-close topics based on last post
FIX: Cursor would stay on lightbox when hitting the back button
rename export/import in favor of backup/restore for better consistency
FIX: BBCode was trimming leading space in `[code]` blocks
copyedits on relative auto-close
remove unnecessary @includes on box-shadow
tweak header box shadow
FIX: all-text site titles were  too wide
add clip to mobile text site title
make editor preview cursor default not i-beam
FIX: css change broke build
Merge pull request #2870 from techAPJ/patch-2

FIX: css change broke build
remove admin-loading in favor of spinner css
remove editor preview css styles from mobile
move editor spinner css to shared (base) css
width 100% for editor on mobile; no preview

also  remove box-sizing mixin, use native CSS3
min-width of 1280px for editor on mobile??

OH HELLllll TO THE NO
minor mobile editor tweaks