bug #971 Fix tag icons after FontAwesome 5.8 upgrade (bocharsky-bw)

This PR was squashed before being merged into the master branch (closes #971).

Discussion
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Fix tag icons after FontAwesome 5.8 upgrade

Fix #970

Now it looks like:
<img width="497" alt="Screen Shot 2019-05-06 at 12 30 41" src="https://user-images.githubusercontent.com/3317635/57217733-166a0780-6ffc-11e9-91d3-767b4d9d1c26.png">

Commits
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e6b77b3 Fix tag icons after FontAwesome 5.8 upgrade

Author: javiereguiluz