add ceo training data as classification input

[dfguerrerom]

This is a WIP. FTM this will be a draft pull request.

The idea of this PR is to add a new feature to SEPAL to retrieve training data for the classification recipe from CEO. Some of the points that we have discussed are:

• Authentication has to be done using the SEPAL ui, users will provide username/password and it will be stored as cookie in user's client (?). SEPAL won't store these credentials.
• After authentication, users will get the list of the projects that they have access (@jonnvega are we also listing public data?).
• User select the project and then the data that want to use.
• We retrieve the data to the client and do some checks and we plug-in to the interface for the csv input.

@jonnvega, this is just an idea, we can shape it more and create some specific tasks?

tasks:

• [ ] : ...

[dfguerrerom]

@jonnvega , do you have the endpoint of CEO to retrieve the projects, and to query the data from it? It would be nice to see an example of the response.