function where(collection, properties, first) {
    return (first && isEmpty(properties))
      ? undefined
      : (first ? find : filter)(collection, properties);
  }
Performs a deep comparison of each element in a `collection` to the given
`properties` object, returning an array of all elements that have equivalent
property values.

@static
@memberOf _
@type Function
@category Collections
@param {Array|Object|string} collection The collection to iterate over.
@param {Object} props The object of property values to filter by.
@returns {Array} Returns a new array of elements that have the given properties.
@example

var characters = [
  { 'name': 'barney', 'age': 36, 'pets': ['hoppy'] },
  { 'name': 'fred',   'age': 40, 'pets': ['baby puss', 'dino'] }
];

_.where(characters, { 'age': 36 });
// => [{ 'name': 'barney', 'age': 36, 'pets': ['hoppy'] }]

_.where(characters, { 'pets': ['dino'] });
// => [{ 'name': 'fred', 'age': 40, 'pets': ['baby puss', 'dino'] }]