Errors: Convert errors to JS objects.

For CLI format as JSON with indent = 2.

lib/index.js

@@ -152,6 +152,12 @@ function getOptions(options) {
   var success = options.success;
 
   options.error = function(err, code) {
+    try {
+      err = JSON.parse(err);
+    } catch (e) {
+      err = { message: err };
+    }
+
     if (error) {
       error(err, code);
     }

lib/render.js

@@ -72,7 +72,7 @@ module.exports = function(options, emitter) {
   };
 
   renderOptions.error = function(error) {
-    emitter.emit('error', chalk.red(error));
+    emitter.emit('error', chalk.red(JSON.stringify(error, null, 2)));
   };
 
   sass.render(renderOptions);