Bump to v4.0.0.

lowerCase.js

@@ -0,0 +1,27 @@
+define(['./internal/createCompounder'], function(createCompounder) {
+
+  /**
+   * Converts `string`, as space separated words, to lower case.
+   *
+   * @static
+   * @memberOf _
+   * @category String
+   * @param {string} [string=''] The string to convert.
+   * @returns {string} Returns the lower cased string.
+   * @example
+   *
+   * _.lowerCase('--Foo-Bar');
+   * // => 'foo bar'
+   *
+   * _.lowerCase('fooBar');
+   * // => 'foo bar'
+   *
+   * _.lowerCase('__FOO_BAR__');
+   * // => 'foo bar'
+   */
+  var lowerCase = createCompounder(function(result, word, index) {
+    return result + (index ? ' ' : '') + word.toLowerCase();
+  });
+
+  return lowerCase;
+});