🧹 update partials to use alt tags for images

This ticket was to confirm that the user can set
the alt text and that it is used in the html. We
discoverd that some of the settable alt text
options are not being used in the html and updated
the ones that were.

- Issue #43

app/views/layouts/homepage.html.erb

@@ -1,7 +1,7 @@
 <% content_for(:navbar) do %>
   <div class="image-masthead">
 <!-- default repository homepage -->
-    <div class="background-container"  title="<%= block_for(name: 'banner_image_text') %>" style="background-image: url('<%= banner_image %>')"></div>
+    <div class="background-container" <%= alt: block_for(name: 'banner_image_text') %> style="background-image: url('<%= banner_image %>')"></div>
     <span class="background-container-gradient"></span>
 
     <div class="container site-title-container">

app/views/themes/cultural_repository/layouts/homepage.html.erb

@@ -2,7 +2,7 @@
 <% content_for(:navbar) do %>
   <div class="image-masthead cultural-homepage">
     <!-- cultural repository homepage -->
-    <div class="background-container" style="background-image: url('<%= banner_image %>')" title="<%= block_for(name: 'banner_image_text') %>"></div>
+    <div class="background-container" style="background-image: url('<%= banner_image %>')" alt="<%= block_for(name: 'banner_image_text') %>"></div>
 
     <div class="container">
       <% if controller_name == 'homepage' %>

app/views/themes/dc_repository/_logo.html.erb

@@ -4,9 +4,9 @@
     <a id="logo" class="navbar-brand d-flex" href="<%= hyrax.root_path %>" data-no-turbolink="true">
       <span class="glyphicon glyphicon-globe" role="img" aria-label="<%= application_name %>" aria-hidden="true"></span>
       <%# OVERRIDE: Hyrax v3.4.1 Change logo image for small screens %>
-      <%= image_tag logo_image, alt_text: block_for(name: 'logo_image_text'), class: "visible-md-lg-xl hidden-sm hidden-xs" %>
+      <%= image_tag logo_image, alt: block_for(name: 'logo_image_text'), class: "visible-md-lg-xl hidden-sm hidden-xs" %>
       <%# OVERRIDE: Hyrax v3.4.1 add image tag for small logo %>
-      <%= image_tag "ut-square", alt_text: block_for(name: 'logo_image_text'), class: "visible-xs-sm hidden-md hidden-lg hidden-xl" %>
+      <%= image_tag "ut-square", alt: block_for(name: 'logo_image_text'), class: "visible-xs-sm hidden-md hidden-lg hidden-xl" %>
     </a>
   <% else %>
     <a id="logo" class="navbar-brand logo d-flex" href="<%= hyrax.root_path %>" data-no-turbolink="true">

app/views/themes/dc_repository/layouts/homepage.html.erb

@@ -3,7 +3,7 @@
 <% content_for(:navbar) do %>
   <div class="image-masthead d-flex">
 <!-- dc-repository homepage -->
-    <div class="background-container"  title="<%= block_for(name: 'banner_image_text') %>" style="background-image: url('<%= banner_image %>')"></div>
+    <div class="background-container" alt="<%= block_for(name: 'banner_image_text') %>" style="background-image: url('<%= banner_image %>')"></div>
     <% # OVERRIDE: Hyrax v3.4.1 - remove background-container-gradient %>
     <% # OVERRIDE: Hyrax v3.4.1 - remove site-title-container %>
     <% # OVERRIDE: Hyrax v3.4.1 - add divs and classes for custom styles %>

app/views/themes/institutional_repository/layouts/homepage.html.erb

@@ -2,7 +2,7 @@
 <% content_for(:navbar) do %>
   <div class="image-masthead">
   <!-- institutional repository homepage -->
-    <div class="background-container" style="background-image: url('<%= banner_image %>')" title="<%= block_for(name: 'banner_image_text') %>"></div>
+    <div class="background-container" style="background-image: url('<%= banner_image %>')" alt="<%= block_for(name: 'banner_image_text') %>"></div>
 
     <div class="container site-title-container">
       <div class="site-title h1" style="text-align: center;">

app/views/themes/neutral_repository/layouts/homepage.html.erb

@@ -2,7 +2,7 @@
 <% content_for(:navbar) do %>
   <div class="image-masthead">
     <!-- neutral repository homepage -->
-    <div class="background-container" title="<%= block_for(name: 'banner_image_text') %>" style="background-image: url('<%= banner_image %>')"></div>
+    <div class="background-container" alt="<%= block_for(name: 'banner_image_text') %>" style="background-image: url('<%= banner_image %>')"></div>
 
     <div class="container site-title-container mb-40">
       <div class="site-title h1" style="text-align: center;">