function findWhere(collection, source) {
      return find(collection, matches(source));
    }
Performs a deep comparison between each element in `collection` and the
source object, returning the first element that has equivalent property
values.

@static
@memberOf _
@category Collection
@param {Array|Object|string} collection The collection to search.
@param {Object} source The object of property values to match.
@returns {*} Returns the matched element, else `undefined`.
@example

var users = [
  { 'user': 'barney', 'age': 36, 'status': 'busy' },
  { 'user': 'fred',   'age': 40, 'status': 'busy' }
];

_.findWhere(users, { 'status': 'busy' });
// => { 'user': 'barney', 'age': 36, 'status': 'busy' }

_.findWhere(users, { 'age': 40 });
// =>  { 'user': 'fred', 'age': 40, 'status': 'busy' }