Add a first pass at jsdoc.

[##130415655] #596

src/core/matchers/toBeGreaterThan.js

@@ -1,5 +1,12 @@
 getJasmineRequireObj().toBeGreaterThan = function() {
-
+  /**
+   * {@link expect} the actual value to be greater than the expected value.
+   * @function
+   * @name matchers#toBeGreaterThan
+   * @param {Number} expected - The value to compare against.
+   * @example
+   * expect(result).toBeGreaterThan(3);
+   */
   function toBeGreaterThan() {
     return {
       compare: function(actual, expected) {