Merge pull request #70 from himorin/wr-c-46-1

added a line at the end of difficulty section (C-46-1)

index.html

@@ -240,7 +240,13 @@ <h3 id="the-difficulties-of-ruby-processing">The difficulties of ruby processing
 case by case as was done in movable type typography.
 It is therefore necessary to decide upon comprehensive rules
 that provide solutions to all the problems listed above,
-so that placement may be determined fully automatically.</p>
+so that placement may be determined fully automatically. 
+The system to be designed needs to be very complex, 
+like ones described in <a href="https://www.w3.org/TR/jlreq/#positioning_of_jukugoruby">Positioning of Jukugo-ruby</a> in [[?JLREQ]], 
+but there exists some remaining issues even with these complex rules. 
+Therefore simple placement rules for fully automatic processing with securing certain level of quality is worth considering, 
+and this document describes one proposal of simple placement rules of Japanese ruby. 
+</p>
 </section>