refactor: Pre-render TeX + MathML server-side to SVG

server/views/pages/view.pug

@@ -18,8 +18,8 @@ block rootNavRight
     a.button.is-outlined(href='/source/' + pageData.meta.path)
       i.nc-icon-outline.education_paper
       span= t('nav.source')
-    //- a.button.is-outlined(href='/hist/' + pageData.meta.path)
-      i.icon-clock
+    a.button.is-outlined(href='/hist/' + pageData.meta.path)
+      i.nc-icon-outline.ui-2_time
       span= t('nav.history')
     if rights.write
       a.button(href='/edit/' + pageData.meta.path)