Rudder

We want to let user be able to add files private to a technique for the technique editor. The simple use case is: "my technique use a template, template and technique live together, they must be packaged together".

First ideas:

- there's two kind of files: text and binary
- we don't want to let big binaries be shared that way, because data duplication will be horrible. So we exclude that case for now (use shared file for that)

On UI, we need:

- to be able to display/add/remove/edit resources managed/linked to the technique,
- reference them in the technique (to access them in generic methods)
- protect them from other techniques (like it's done for manually created technique in rudder)

We also need to:

- correctly adpate the technique save to also take care of these files (copy in correct destination...)
- update generated metadata.xml