added two more more character entities sets
added two more more character entities sets

http://www.w3.org/TR/xhtml1/dtds.html#h-A2

Special characters
* http://www.w3.org/TR/xhtml1/DTD/xhtml-special.ent

Symbols
* http://www.w3.org/TR/xhtml1/DTD/xhtml-symbol.ent
concord-consortium/rigse,concord-consortium/rigse,concord-consortium/rigse,concord-consortium/rigse,concord-consortium/rigse,concord-consortium/rigse