Patch for fixing spacing problem on CJK language. (#5855)

This changes the default on the xeCJK package so that spaces between words
are preserved instead of being collapsed. This is necessary for Korean.

Issue and solution is from below.
https://tex.stackexchange.com/questions/17292/how-to-write-spaces-between-korean-words-with-xecjk

data/templates/default.latex

@@ -137,7 +137,7 @@ $endif$
 $endif$
 $if(CJKmainfont)$
   \ifxetex
-    \usepackage{xeCJK}
+    \usepackage[space]{xeCJK}
     \setCJKmainfont[$for(CJKoptions)$$CJKoptions$$sep$,$endfor$]{$CJKmainfont$}
   \fi
 $endif$