Implemented ImageUpload widget that uses Blobstore and other fixes

- Implemented ImageUpload widget
- ImageUploadServlet now uses GAE blobstore
- GetImageServlet now returns the image meta object and redirects to its
url
- JDO Moved server.entities to shared.domain
- Moved Beer DTO generating class to DTO
- Fixed indentation on some files
- Removed GWT dev dependency
tidyURL now uses port variable