Footnote markup shouldn't be interpreted as new slides

Addresses #4

layouts/partials/reveal-hugo/slides.html

@@ -5,14 +5,16 @@
     {{ range . -}}
     <!-- Don't process empty content files -->
       {{- if ne (len .Content) 0 -}}
+        <!-- Remove the <hr /> tag generated by blackfriday for footnotes -->
+        {{ $content := replace .Content "<div class=\"footnotes\">\n\n<hr />" "<div class=\"footnotes\">" }}
         <!-- Split the processed content by <hr /> tag -->
-        {{- range (split .Content "<hr />") -}}
+        {{- range (split $content "<hr />") -}}
           <!-- Only wrap in <section> tag if not already wrapped by shortcode -->
           {{- if in . "data-noprocess" -}}
             {{- . | safeHTML -}}
           {{- else -}}
             <section>
-              {{ . | safeHTML }}
+              {{- . | safeHTML }}
             </section>
           {{ end -}}
         {{- end -}}