add ESC key functionality to forgot password modal

lms/templates/forgot_password_modal.html

@@ -75,5 +75,15 @@
     cycle_modal_tab("#pwd_reset_email", "#pwd_reset_button")
     cycle_modal_tab("#pwd_reset_button", "#forgot-password-modal .close-modal")
 
+    // Hitting the ESC key will exit the modal
+    $("#forgot-password-modal").on("keydown", function(e) {
+        var keyCode = e.keyCode || e.which;
+        // 27 is the ESC key
+        if (keyCode === 27) {
+            e.preventDefault();
+            $("#forgot-password-modal .close-modal").click();
+        }
+    });
+
   })(this)
 </script>