导入module

1、http://blog.csdn.net/cryssdut/article/details/50357876

2、直接把lib复制黏贴到项目里，无法直接用；需要在 settings.gradle中加入：

include ':app',':MPChartLib'
重新编译即可；

会在app底下的build.gradle文件中添加 compile project(path: ':MPChartLib')

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.4.0'
    compile project(path: ':MPChartLib')
}