Add ability to add site description below company name. Fixes #2

exampleSite/config.toml

@@ -2,3 +2,5 @@ baseURL = "http://example.org/"
 languageCode = "en-us"
 title = "Awesome Lighting Inc."
 theme = "hugo-shopping-product-catalogue-simple"
+[Params]
+description = ""

layouts/partials/products/list/product-list.html

@@ -1,5 +1,6 @@
 <header>
     <h1 class="text-center">{{ .Site.Title }}</h1>
+    {{ with .Site.Params.description }}<h4 class="text-center">{{ . }}</h4>{{ end }}
 </header>
 <article class="container-fluid">
     <div class="row">

layouts/products/single.html

@@ -1,6 +1,7 @@
 {{ define "main" }}
 <header>
     <h1 class="text-center">{{ .Site.Title }}</h1>
+    {{ with .Site.Params.description }}<h4 class="text-center">{{ . }}</h4>{{ end }}
 </header>
 <article class="container-fluid">
     <div class="row">