Add function mergeFilename


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4680 dfc29bdd-3216-0410-991c-e03cc46cb475
Add tests for mergeFilename.


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4681 dfc29bdd-3216-0410-991c-e03cc46cb475
Bugfix: getFont for xml-fonts now also works for fonts inside archives (thx @Neirdan for bugreport)


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4682 dfc29bdd-3216-0410-991c-e03cc46cb475
update changes.txt


git-svn-id: svn://svn.code.sf.net/p/irrlicht/code@4683 dfc29bdd-3216-0410-991c-e03cc46cb475