[WIP] Zxp-provider can return a cmd/a path to ZXPSignCmd tool.

- Cut and pass correctly command and arguments to spawn command
- Otherwise works like before

tasks/lib/zxp.js

@@ -85,15 +85,24 @@ module.exports = function (grunt)
             grunt.fatal('Invalid input folder.');
         }
 
-        var spawn_options = {
-            cmd: zxp_path,
-                args: [
+		var zxp_path_arr = zxp_path.split(" ");
+		var sign_args = [
                     '-sign',
                     input_folder,
                     output_file,
                     options['package'].certificate.file,
                     options['package'].certificate.password,
-                ],
+                ];
+
+		if (zxp_path_arr.length > 1) {
+			for (var i = 1; i < zxp_path_arr.length; i++) {
+				sign_args.unshift(zxp_path_arr[i]);
+			}
+		}
+
+        var spawn_options = {
+            cmd: zxp_path_arr[0],
+                args: sign_args
             },
             errors = [];