fix(cli): report gulpfile errors

Author: tlancina

lib/cli.js

@@ -235,17 +235,20 @@ function loadGulpfile(){
       require(path.resolve(process.cwd() + '/' + names[i]));
       return true;
     } catch(e){
-      if (e instanceof SyntaxError) {
-        console.error('\nThere is a syntax error in your gulpfile:');
-        console.error(e.message)
-        process.exit(1);
-      }
-      if (e.code === 'MODULE_NOT_FOUND' && e.message.indexOf(names[i]) === -1) {
-        console.log('Uh oh! Looks like you\'re missing a module in your gulpfile:');
-        console.error(e.message);
-        console.log('\nDo you need to run `npm install`?\n');
-        process.exit(1);
+      if (e.code === 'MODULE_NOT_FOUND') {
+        if (e.message.indexOf(names[i]) === -1) {
+          console.log('Uh oh! Looks like you\'re missing a module in your gulpfile:');
+          console.error(e.message);
+          console.log('\nDo you need to run `npm install`?\n');
+          process.exit(1);
+        } else {
+          // ignore missing gulpfile
+          continue
+        }
       }
+      console.error('There is an error in your gulpfile: ')
+      console.error(e.stack);
+      process.exit(1);
     }
   }
   return false;