Better docs in studio view

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+  <p> This XBlock allows you to collect student feedback on pieces of
+    the course. This may be helpful either for course improvement, or
+    to give students a chance to reflect on what they have done.</p>
+  <p>Please note that the feedback needs to be analyzed as part of
+    the <a href="https://edx.readthedocs.org/en/latest/">edX research
+    dumps</a>. For now, we do not provide any kind of visual analytics
+    associated with this block.</p>
+  <p>We do recommend matrix sampling. This can be done by using the
+  <a href="http://edx.readthedocs.org/projects/edx-partner-course-staff/en/latest/content_experiments/content_experiments_configure.html">randomized
+  control trials framework</a>.</p>
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