Add alt attributes for images

src/_data/highlights.yml

@@ -1,6 +1,7 @@
 - title: Ruby on Rails Contracting
   message_header_class: ruby-red
   logo: ruby-on-rails-logo.png
+  logo_alt: Ruby on Rails Logo
   show_recommendations: true
   description: |
     Leverage the power of Ruby and Rails to build scalable applications quickly. Looking for an architect to 
@@ -12,6 +13,7 @@
   message_class: is-primary
   message_header_class: has-text-white
   logo: rubygems_logo_red.png
+  logo_alt: RubyGems Logo
   description: |
     Simplify and speed development of Rails controllers by making filter parameters declarative
     with [the Filterameter gem](https://github.com/RockSolt/filterameter).

src/_layouts/home.erb

@@ -13,7 +13,7 @@ layout: default
     <div class="column is-three-fifths-desktop is-half-tablet">
       <article class="box">
         <h1 class="title is-4"><%= data.title %></h1>
-        <img src="<%= data.image %>">
+        <img src="<%= data.image %>" alt="<%= data.image_alt %>">
         <div class="content">
           <%= yield %>
         </div>

src/_partials/_highlight.erb

@@ -5,7 +5,7 @@
   </div>
 
   <div class="message-body content">
-    <img src="images/<%= highlight.logo %>" class="highlight-logo">
+    <img src="images/<%= highlight.logo %>" class="highlight-logo" alt="<%= highlight.logo_alt %>">
     <%= markdownify highlight.description %>
 
     <%# this is pretty specific to the contracting highlight for now %>

src/_partials/_member_profile.erb

@@ -14,13 +14,13 @@
   </div>
   <div class="card-footer">
     <a href="<%= member.linked_in %>" class="card-footer-item">
-      <img src="images/LI-In-Bug.png" class="linked-in-logo">
+      <img src="images/LI-In-Bug.png" class="linked-in-logo" alt="LinkedIn Logo">
     </a>
     <a href="<%= member.github %>" class="card-footer-item">
-      <img src="images/github-mark.png" class="github icon">
+      <img src="images/github-mark.png" class="github icon" alt="GitHub Logo">
     </a>
     <a href="mailto:<%= member.email %>" class="card-footer-item">
-      <img src="images/mail.png" class="icon">
+      <img src="images/mail.png" class="icon" alt="Email icon">
     </a>
   </div>
 </div>

src/index.md

@@ -2,6 +2,7 @@
 layout: home
 title: The Story of Software
 image: "images/once-upon-a-time.jpg"
+image_alt: "pen writing 'Once upon a time'"
 description: |
   Rockridge Solutions is a boutique software consulting firm that has been helping clients tell
   the story of their businesses for 20 years. Let Todd and John leverage the power of Ruby on