remove podlove-font from libraries

In order to streamline update processes the podlove-font will be
installed using bower.
add podlove-font to bower dependencies
change fontpath in gulpfile
include new font CSS in main SASS source
map icon CSS classnames to match new font

hide sharing options without icons (gplus and facebook)
Merge pull request #186 from podlove/new-icon-font

Use new icon font