Add sax test from Stanislav O.Pogrebnyak.
Add sax test from Stanislav O.Pogrebnyak.

increments/libxml-ruby,sferik/libxml-ruby,sferik/libxml-ruby,increments/libxml-ruby,sferik/libxml-ruby,xml4r/libxml-ruby,sferik/libxml-ruby,xml4r/libxml-ruby,sferik/libxml-ruby,increments/libxml-ruby,xml4r/libxml-ruby,sferik/libxml-ruby