$http.get('/events.json').then(parseDates);

parseDates.js

function parseDates(response) {
	response.data.forEach(function (object) {
		Object.keys(object).forEach(function (key) {
			var
			value = object[key],
			isDate = /^\d\d\d\d-\d\d-\d\dT\d\d:\d\d:\d\d\.\d\d\dZ$/.test(value);

			if (isDate) {
				object[key] = new Date(value);
			}
		});
	});
	
	// uh, return a promise
}