Remove unused class styling (#560)

Author: jarrodmillman

layouts/partials/section/section.html

@@ -3,7 +3,7 @@
   {{ partial "breadcrumbs.html" . }}
   <h1>{{ .Title }}</h1>
   {{ if .Params.Subtitle }}
-  <h5 class="subtitle is-5 is-muted">{{ .Params.Subtitle }}</h5>
+  <h5 class="subtitle">{{ .Params.Subtitle }}</h5>
   {{ end }}
   {{ if .Content }}
   {{ .Content }}