Rename images.gtk|gdiplus|cocoa to images.loader.*. Fixes #176.

basis/images/loader/cocoa/cocoa.factor

@@ -5,7 +5,7 @@ combinators core-foundation.data core-graphics
 core-graphics.types fry locals images images.loader io kernel
 math sequences ;
 FROM: system => os macosx? ;
-IN: images.cocoa
+IN: images.loader.cocoa
 
 SINGLETON: ns-image
 

basis/images/loader/gdiplus/gdiplus.factor

@@ -4,7 +4,7 @@ classes.struct destructors images images.loader kernel locals
 math windows.com windows.gdiplus windows.streams windows.types
 typed byte-arrays grouping sequences ;
 FROM: system => os windows? ;
-IN: images.gdiplus
+IN: images.loader.gdiplus
 
 SINGLETON: gdi+-image
 

basis/images/loader/gtk/gtk.factor

@@ -5,7 +5,7 @@ destructors gdk.pixbuf.ffi gobject.ffi grouping images
 images.loader io kernel locals math sequences
 specialized-arrays ;
 FROM: system => os linux freebsd netbsd openbsd ;
-IN: images.gtk
+IN: images.loader.gtk
 SPECIALIZED-ARRAY: uchar
 
 SINGLETON: gtk-image

basis/ui/images/images.factor

@@ -33,8 +33,8 @@ PRIVATE>
 
 <<
 {
-    { [ os macosx? ] [ "images.cocoa"   require ] }
-    { [ os windows?  ] [ "images.gdiplus" require ] }
-    [ "images.gtk" require ]
+    { [ os macosx? ] [ "images.loader.cocoa"   require ] }
+    { [ os windows?  ] [ "images.loader.gdiplus" require ] }
+    [ "images.loader.gtk" require ]
 } cond
 >>