Fix Maruku Hanging Bug

A Maruku-syntax <div> with an unclosed IAL (and, it seems, at least one equation)
would cause Instiki to hang. Badly. Requiring a 'kill -9' to terminate it.
Reverting the OpenDiv and CloseDiv Regexps to my, more simple-minded, versions
fixes the problem.

vendor/plugins/maruku/lib/maruku/ext/div.rb

@@ -10,11 +10,28 @@
 #| +--------------------------------------------------
 #+---------------------------------------------------
 
-OpenDiv = /^[ ]{0,3}\+\-\-+\s*(\{([^{}]*|".*"|'.*')*\})?\s*\-*\s*$/
-CloseDiv = /^[ ]{0,3}\=\-\-+\s*(\{([^{}]*|".*"|'.*')*\})?\s*\-*\s*$/
-# note these are not enough for parsing the above example:
-#OpenDiv = /^[ ]{0,3}\+\-\-+\s*(.*)$/
-#CloseDiv = /^[ ]{0,3}\=\-\-+\s*(.*)$/
+## These cause Instiki to hang when it encounters
+##
+##   +-- 
+##   ###### Definition
+##   A _Froelicher Space_ is a triple $(X,C_X,F_X)$ 
+##   =-- {: .num_defn #FroelicherSpace
+##
+## or
+##
+##   +-- {: .num_defn #FroelicherSpace
+##   ###### Definition
+##   A _Froelicher Space_ is a triple $(X,C_X,F_X)$ 
+##   =--
+#
+#OpenDiv = /^[ ]{0,3}\+\-\-+\s*(\{([^{}]*|".*"|'.*')*\})?\s*\-*\s*$/
+#CloseDiv = /^[ ]{0,3}\=\-\-+\s*(\{([^{}]*|".*"|'.*')*\})?\s*\-*\s*$/
+#
+## note these are not enough for parsing the above example:
+## (but they don't produce a hang ...)
+#
+OpenDiv = /^[ ]{0,3}\+\-\-+\s*(.*)$/
+CloseDiv = /^[ ]{0,3}\=\-\-+\s*(.*)$/
 StartPipe = /^[ ]{0,3}\|(.*)$/ # $1 is rest of line
 DecorativeClosing = OpenDiv