Add support for sample data files

[layerzerolabs]

it should generate this sort of thing if you have sample files in a certain place with a certain name.

module.exports.getInterventionsFromInstantSession = function(req, params, callback) {
var response = JSON.parse(require('fs.extra').readFileSync(__dirname+'/../../public/sampledata /instant/interventions.json', {encoding: 'utf8'}));
return callback(null, response);
};

[layerzerolabs]

It could also generate tests which make sure it provides the sample data given certain path params