Use const_cast<> instead of C cast for clarity
Use const_cast<> instead of C cast for clarity

No real changes, just use a more appropriate cast which already has a
nice side-effect of not resulting in gcc -Wcast-qual warnings.

vslavik/xmlwrapp,vslavik/xmlwrapp,vadz/xmlwrapp,vadz/xmlwrapp,vslavik/xmlwrapp,vadz/xmlwrapp