Style the print button, resolves #656. (#657)

Author: lucaboesch

templates/reportpage.mustache

@@ -83,7 +83,7 @@
         {{#responses}}{{{.}}}{{/responses}}
         {{#bottomnavigationbar}}<div class="box respondentsnavbar">{{{.}}}</div>{{/bottomnavigationbar}}
         {{#printparam}}
-            <button id="print-button" title="{{#str}}print, mod_questionnaire{{/str}}">
+            <button id="print-button" class="btn btn-primary" title="{{#str}}print, mod_questionnaire{{/str}}">
                     {{#str}}printbutton, mod_questionnaire{{/str}}
             </button>
         {{/printparam}}