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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2a0729e Fix tag icons after FontAwesome 5.8 upgrade

Author: javiereguiluz

assets/scss/bootstrap-tagsinput.scss

@@ -49,7 +49,8 @@
 }
 .tt-suggestion.tt-selectable:before {
   content: '\f02b';
-  font-family: 'FontAwesome';
+  font-family: 'Font Awesome 5 Free';
+  font-weight: 900;
   display: inline-block;
   font-size: 15px;
   margin-right: 0.5em;
@@ -172,7 +173,8 @@
 }
 .bootstrap-tagsinput .tag:before {
   content: '\f02b';
-  font-family: 'FontAwesome';
+  font-family: 'Font Awesome 5 Free';
+  font-weight: 900;
   display: inline-block;
   font-size: 15px;
   margin-right: 0.5em;
@@ -182,7 +184,8 @@
 }
 .bootstrap-tagsinput .tag [data-role="remove"]:after {
   content: '\f00d';
-  font-family: 'FontAwesome';
+  font-family: 'Font Awesome 5 Free';
+  font-weight: 900;
   display: block;
   font-size: 13px;
   color: #fff;