update holder.js image dimensions for sizing example
update holder.js image dimensions for sizing example

* update holder.js image dimensions for sizing example
  * use `100%` instead of `100%`
  * :memo: https://github.com/imsky/holder#fluid-placeholders

coliff/bootstrap,nice-fungal/bootstrap,stanwmusic/bootstrap,gijsbotje/bootstrap,m5o/bootstrap,stanwmusic/bootstrap,bardiharborow/bootstrap,tagliala/bootstrap,yuyokk/bootstrap,tjkohli/bootstrap,gijsbotje/bootstrap,stanwmusic/bootstrap,tagliala/bootstrap,twbs/bootstrap,nice-fungal/bootstrap,kvlsrg/bootstrap,bardiharborow/bootstrap,bardiharborow/bootstrap,zalog/bootstrap,twbs/bootstrap,peterblazejewicz/bootstrap,peterblazejewicz/bootstrap,gijsbotje/bootstrap,inway/bootstrap,tjkohli/bootstrap,coliff/bootstrap,bardiharborow/bootstrap,inway/bootstrap,GerHobbelt/bootstrap,fschumann1211/bootstrap,fschumann1211/bootstrap,GerHobbelt/bootstrap,tagliala/bootstrap,fschumann1211/bootstrap,inway/bootstrap,GerHobbelt/bootstrap,zalog/bootstrap,stanwmusic/bootstrap,yuyokk/bootstrap,peterblazejewicz/bootstrap,kvlsrg/bootstrap,kvlsrg/bootstrap,fschumann1211/bootstrap,m5o/bootstrap,yuyokk/bootstrap,zalog/bootstrap,yuyokk/bootstrap,gijsbotje/bootstrap,nice-fungal/bootstrap