better entropy colors and optional callback, thanks Niphlod

VERSION

@@ -1 +1 @@
-Version 2.0.9 (2012-09-23 16:58:06) stable
+Version 2.0.9 (2012-09-23 17:00:31) stable

applications/welcome/static/js/web2py.js

@@ -191,8 +191,7 @@ function web2py_validate_entropy(myfield, req_entropy) {
         var v = (web2py_calc_entropy(myfield.val())||0)/req_entropy;
         var r=0,g=0,b=0,rs=function(x){return Math.round(x*15).toString(16)};
 	if(v<=0.5) {r=1.0; g=2.0*v;}
-	else if(v<1.0) {r=(1.0-2.0*(v-0.5)); g=1.0;}
-	else {g=Math.max(0,2.0-v); b=1.0;}
+	else {r=(1.0-2.0*(Math.max(v,0)-0.5)); g=1.0;}
 	var color = '#'+rs(r)+rs(g)+rs(b);
         myfield.css('background-color',color);
 	entroy_callback = myfield.attr('entroy_callback');