[build] added gulp builder

tasks/download.js

@@ -0,0 +1,24 @@
+'use strict';
+const path = require('path');
+const request = require('request');
+const progress = require('request-progress');
+const source = require('vinyl-source-stream');
+const gutil = require('gulp-util');
+
+
+module.exports = (url) => {
+    const name = path.basename(url);
+    let stream = null;
+    return stream = progress(request({url: url, encoding: null}, function(error, response, body) {
+        try {
+            if (error) throw error;
+            if (response.statusCode !== 200) throw `${response.statusCode} ${response.statusMessage}`;
+        } catch (e) {
+            this.emit('error', new gutil.PluginError({plugin: 'download', message: e}));
+        }
+    }))
+        .on('error', (e) => stream.emit('error', e))
+        .on('progress', (p) => stream.emit('progress', p))
+        .pipe(source(name));
+};
+