Display copyright notice on mentoring/step block.

A small light grey copyright notice is displayed below the buttons
of mentoring and step blocks.

It is hidden in the apros theme.

problem_builder/public/css/problem-builder.css

@@ -249,3 +249,14 @@
     background-color: white;
     box-shadow: 0 10px 20px #5C5C5C;
 }
+
+.mentoring .copyright {
+    color: #AAA;
+    clear: both;
+    font-size: 10px;
+    margin: 3em 0;
+}
+
+.mentoring .copyright a {
+    color: #69C0E8;
+}

problem_builder/public/themes/apros.css

@@ -26,3 +26,7 @@
     margin-left: 1.8em;
     padding-left: 0;
 }
+
+.themed-xblock.mentoring .copyright {
+    display: none;
+}

problem_builder/templates/html/mentoring.html

@@ -56,4 +56,9 @@
     <div class="assessment-review-tips"></div>
   </div>
   <div class="review-link"><a href="#">Review final grade</a></div>
+
+  <p class="copyright">
+    Copyright &copy; 2013&ndash;2015 OpenCraft, Harvard, edX, McKinsey, and The People's Science, released under the
+    <a target="_blank" href="https://github.com/open-craft/problem-builder/blob/master/LICENSE">APGLv3 license</a>
+  </p>
 </div>

problem_builder/templates/html/mentoring_with_steps.html

@@ -28,4 +28,9 @@
 
   <div class="review-link"><a href="#">Review final grade</a></div>
 
+  <p class="copyright">
+    Copyright &copy; 2013&ndash;2015 OpenCraft, Harvard, edX, McKinsey, and The People's Science, released under the
+    <a target="_blank" href="https://github.com/open-craft/problem-builder/blob/master/LICENSE">APGLv3 license</a>
+  </p>
+
 </div>