Add a button in the list to remove a protobuf schema

https://marvelapp.com/56f8eca/screen/68146471

A confirmation should be asked

https://marvelapp.com/56f8eca/screen/68146472

When the file is removed, display a confirmation notification. The file is not longer in the list

https://marvelapp.com/56f8eca/screen/68146473