build: add weex factory dev script

package.json

@@ -19,7 +19,8 @@
     "dev:test": "karma start test/unit/karma.dev.config.js",
     "dev:ssr": "rollup -w -c build/config.js --environment TARGET:web-server-renderer",
     "dev:compiler": "rollup -w -c build/config.js --environment TARGET:web-compiler ",
-    "dev:weex": "rollup -w -c build/config.js --environment TARGET:weex-framework ",
+    "dev:weex": "rollup -w -c build/config.js --environment TARGET:weex-framework",
+    "dev:weex:factory": "rollup -w -c build/config.js --environment TARGET:weex-factory",
     "dev:weex:compiler": "rollup -w -c build/config.js --environment TARGET:weex-compiler ",
     "build": "node build/build.js",
     "build:ssr": "npm run build -- web-runtime-cjs,web-server-renderer",