add sass/functions/element-category that provides name of whole elements based on category
rename sass/mixins/category to "elements", sass/mixins/category to "sectionize".
make sectionize() to accept omittable args to specify optional selector syntax and !important.
make elements-*() to use element-category() functions.
add sass/appearance/
make sass/mixins/reset to use element-category() functions.
add sass/greedy for use to import Greedy!
fix syntax error. and take somewhat changes
discard media-font-fixity-width(), instead add media-fix-font-min() and media-fix-font-max().
configure to use experimental features on gecko.