optimization level is taken from env now

lib/less/parser.js

@@ -155,14 +155,14 @@ less.Parser = function Parser(env) {
         }
     }
 
+    this.env = env || {};
 
     // The optimization level dictates the thoroughness of the parser,
     // the lower the number, the less nodes it will create in the tree.
     // This could matter for debugging, or if you want to access
     // the individual nodes in the tree.
-    this.optimization = 2;
+    this.optimization = this.env.optimization || 2;
 
-    this.env = env || {};
 
     //
     // The Parser