Add option to globally disable single page social share

Signed-off-by: Marek Pikuła <[email protected]>

exampleSite/config.yaml

@@ -385,6 +385,7 @@ params:
       content: "min read"
     scrollprogress:
       enable: true
+    socialShare: true
 
   # For translations
   terms:

layouts/_default/single.html

@@ -64,7 +64,7 @@
           </aside>
           {{end}}
 
-          {{ if .Params.socialShare | default true }}
+          {{ if .Params.socialShare | default .Site.Params.singlePages.socialShare | default true }}
           <aside class="social">
             <h5>{{ .Site.Params.terms.social | default "Social" }}</h5>
             <div class="social-content">