Creative: Override the hand instead of re-registering

Allows the initial hand registration to alter the 'wield_scale' without
needing to also alter it in creative mod.
Also make default mod a dependency again, as the initial hand
registration is required.

mods/creative/mod.conf

@@ -1,4 +1,3 @@
 name = creative
 description = Minetest Game mod: creative
-depends = sfinv
-optional_depends = default
+depends = default, sfinv