WIP: Use bootstrap-sass

WIP: Use bootstrap-sass
Merge remote-tracking branch 'origin/master' into bootstrap-sass
fixed for bootstrap-sass & fixed width
merged master
fixed css class: .hide => .d-none
Update phantom helpers
fixed for icons
WIP: add font-awesome
fixed for production: added import bootstrap/glyphicons
fixed gaku.css.scss
mini fix
Merge pull request #250 from Genshin/bootstrap-sass

Modified to use bootstrap-sass