Some save() methods have arguments and shouldn't

File is probably fine but user/server should _not_ have them
```
λ grep -R 'def save([a-z ]' .
./lib/fog/google/models/sql/user.rb:        def save(password: nil)
./lib/fog/storage/google_xml/models/file.rb:        def save(options = {})
./lib/fog/compute/google/models/server.rb:        def save(username: nil, public_key: nil)
```