Resolution to #7

Fault in gf256 multiply function.
Atom removed a bunch of trailing spaces, so these are in here too.

src/gf256.erl

@@ -83,10 +83,10 @@ subtract(F = #gf256{}, A, B) ->
 	add(F, A, B).
 
 %%
-multiply(#gf256{}, 1, B) ->
-	B;
-multiply(#gf256{}, A, 1) ->
-	A;
+multiply(#gf256{}, 0, _) ->
+	0;
+multiply(#gf256{}, _, 0) ->
+	0;
 multiply(F = #gf256{}, A, B) ->
 	X = (log(F, A) + log(F, B)) rem ?RANGE,
 	exponent(F, X).