Removed all references to using namespace std to help solve compilation problems

under Windows and IRIX.

Also integrated small change to lib3ds from Drew for IRIX compilation.

src/osgText/FTGLTextureFont.cpp

@@ -2,8 +2,6 @@
 #include	"FTGlyphContainer.h"
 #include	"FTTextureGlyph.h"
 
-using namespace std;
-
 inline GLuint NextPowerOf2( GLuint in)
 {
      in -= 1;