Has never been easier to read, view, modify sandbox file

1. view, modify files in sandbox;
2. upload new file to app;
3. support many formats, such as plain text, xml, json, js, image, sqlite (suffix of sqlite file should be: .db,.sqlite or.database);
4. support multiple devices, and multiple apps in the same device;
5. file monitor, we can observe file changes such as add, edit, remove in realtime.