Extend Content Loader Framework to support delegating to another model for content preparation

[natacha-beck]

We need to add a :delegate optional parameter to has_content in model (mostly collections) that will use the class method of the model to prepare the content to be sent to the browser.

Example:
In civet collection
has_content :method => :get_raw_data, :delegate_to Minc, :type => :text

the content action will then pass the path of the file in the collection to the class method in Minc and return the data to the browser.

If :delegate_to is not present it should call the instance method that then calls the class method with self.cache_full_path

Redmine: 3098

[natacha-beck]

@prioux the idea was implemented in the SubViewer mechanism no ?
So we can close ?

[prioux]

No I don't think we have this yet.