Add buymeacoffee.com widget (#707)

Co-authored-by: Emruz Hossain <hossainemruz@gmail.com>

layouts/partials/misc/support.html

@@ -12,5 +12,9 @@
             });
             </script>
         {{ end }}
+        <!-- Enable Buy Me a Coffee (buymeacoffee.com) floating button -->
+        {{ with .buymeacoffee }}              
+          <script data-name="BMC-Widget" data-cfasync="false" src="https://cdnjs.buymeacoffee.com/1.0.0/widget.prod.min.js" data-id="{{ .user }}" data-description="{{ .text }}" data-message="{{ .info }}" data-color="{{ .color }}" data-position="Right" data-x_margin="10" data-y_margin="18"></script>
+        {{ end }}
     {{ end }}
 {{ end }}