Add Iconify support

[giterlizzi]

Iconify includes over 40000 icons from popular fonts and emoji icon sets (like Font Awesome 4 & 5, Material Design Icons, Noto and more). Iconify load on demand the icons present on the page instead of all icons in Webfonts icons (FontAwesome & co.). This approac reduce the size of downloaded assets (.ttf, .eot, .woff, etc.) and speedup the rendering of the page.

The syntax are the same of Icon plugin:

{{icon>pack:icon-name?size&flag}}

#11 #20 #18
giterlizzi/dokuwiki-template-bootstrap3#442
giterlizzi/dokuwiki-template-bootstrap3#428

[ParoTheParrot]

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