Create summary export

[jen-thomas]

Currently all export options, export all responses to the questions, e.g. http://86.119.31.38:8752/projects/1/answers/

For the reviewers, it would be useful to have a summary of this information which contains a summary of the datasets that will be produced and some higher-level information about what is intended to be done with the data (particularly that which is targeted towards the evaluation point for the full proposal).

Further details of precisely which fields need to be exported for this summary still need to be defined.