Add field in SaveFile_Request to save speos light box from scene

[bgonzalezacevedo]

The aim of this PR is to improve the service SceneActions::SaveFile in order to save a scene into speos light box.

We add following fiel in SaveFile_Request message:

• password - Password that we want to protect the speos lightbox file with a password
• is_black_boxed - Flag to save the scene into black-boxed speos lightbox. If the scene is already tagged as black-boxed, this flag is ignored (ex: scene loaded from black-boxed speos light box)

These fields are only necessary if user want save a speos light box.