Bug 21407: Can't enter new macros in the advanced cataloging editor (rancor)

Bug 21407: Can't enter new macros in the advanced cataloging editor (rancor)

This patch upgrades Codemirror to the latest version (5.40.2). Doing so
fixes a problem with the advanced cataloging editor's macro editor which
appears in the latest version of Firefox (62): The first line of the
macro editor is not visible.

To test, apply the patch and clear your browser cache if necessary.
EnableAdvancedCatalogingEditor must be set to "Enable."

- Go to Cataloging -> Advanced editor.
- Click the "Macros" toolbar button.
- In the main part of this modal window you should see a blank line
  marked "1."
- Click "New macro..."
- The editor's line 1 should now be editable. Enter text to confirm that
  it works correctly.

Signed-off-by: Michal Denar <black23@gmail.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>