Rewrote image search

This code is more generic and support all cases. Previously
we had bug where the user lost his image path if the image
was not located in image directory.

gns3server/modules/qemu/__init__.py

@@ -112,3 +112,9 @@ class Qemu(BaseManager):
         """
 
         return os.path.join("qemu", "vm-{}".format(legacy_vm_id))
+
+    def get_images_directory(self):
+        """
+        Return the full path of the images directory on disk
+        """
+        return os.path.join(os.path.expanduser(self.config.get_section_config("Server").get("images_path", "~/GNS3/images")), "QEMU")