update build shell

build/build.sh

 #!/bin/bash
 
-cd ../
+
+basePath=$(cd `dirname $0`; pwd)
+cd ${basePath}/../
 rm -r dist
 
 npm run prepublish
-webpack
-webpack -p
-webpack --config extension/webpack.config.js
-webpack --config extension/webpack.config.js -p
\ No newline at end of file
+
+./node_modules/.bin/webpack
+./node_modules/.bin/webpack -p
+./node_modules/.bin/webpack --config extension/webpack.config.js
+./node_modules/.bin/webpack --config extension/webpack.config.js -p
+
+