- anonym XFile materials are named now, to prevent them from being merged somehow

- added another boost dependency - lexical_cast - and a little replacement for all those boost haters out there

git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@826 67173fc5-114c-0410-ac8e-9d2fd5bffc1f

code/XFileParser.cpp

@@ -710,6 +710,8 @@ void XFileParser::ParseDataObjectMaterial( Material* pMaterial)
 {
 	std::string matName;
 	readHeadOfDataObject( &matName);
+	if( matName.empty())
+		matName = std::string( "material") + boost::lexical_cast<std::string>( mLineNumber);
 	pMaterial->mName = matName;
 	pMaterial->mIsReference = false;