plantuml：壹個用來繪制UML圖的Java類庫。支持的UML圖包括：時序圖、用例圖、類圖、組件圖、活動圖
On Mac: go to Android
Studio -> Preferences -> Plugins
註：On Windows: go to Android
Studio -> File -> Settings -> Plugins
配置android studio
註意：
/usr/bin/neato for linux
/usr/local/bin/neato for mac osx