Add method to move file on remote, to be used with an event subsciber

Problem/Motivation

In some cases it could be handy to perform some custom operation on the remote, that are too specific for the generic use case of the module, like moving imported files instead or deleting, but there could be other scenarios.

Instead of adding further options on the form, we could simply add an event system in order top intercept and modify the regular behavior.

We could also add extra operations to the DataSource interface, in order to be used in the dispatched events.

Proposed resolution

- [ ] add hooks or event dispatch
- [ ] add extra custom operations (like move or copy)

Remaining tasks

TBC

User interface changes

None

API changes

Addition of few event subscribers (to be determined)

Data model changes

None