Fix case-sensitivity change behaviour.

See https://svn.boost.org/trac/boost/ticket/11205.
Update docs to match.

doc/html/boost_regex/background_information/history.html

@@ -39,9 +39,14 @@
 <a name="boost_regex.background_information.history.h0"></a>
         <span class="phrase"><a name="boost_regex.background_information.history.boost_regex_5_1_1"></a></span><a class="link" href="history.html#boost_regex.background_information.history.boost_regex_5_1_1">Boost.Regex-5.1.1</a>
       </h5>
-<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
+<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
+<li class="listitem">
             Change to lockfree implementation of memory cache, see <a href="https://github.com/boostorg/regex/pull/23" target="_top">PR#23</a>.
-          </li></ul></div>
+          </li>
+<li class="listitem">
+            Fix bug in case sensitivity change, see <a href="https://svn.boost.org/trac/boost/ticket/11940" target="_top">#11940</a>.
+          </li>
+</ul></div>
 <h5>
 <a name="boost_regex.background_information.history.h1"></a>
         <span class="phrase"><a name="boost_regex.background_information.history.boost_regex_5_1_0_boost_1_60_0"></a></span><a class="link" href="history.html#boost_regex.background_information.history.boost_regex_5_1_0_boost_1_60_0">Boost.Regex-5.1.0

doc/html/index.html

@@ -221,7 +221,7 @@
   </p>
 </div>
 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
-<td align="left"><p><small>Last revised: March 12, 2016 at 19:00:00 GMT</small></p></td>
+<td align="left"><p><small>Last revised: March 14, 2016 at 19:20:20 GMT</small></p></td>
 <td align="right"><div class="copyright-footer"></div></td>
 </tr></table>
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