Bug 9618: (follow-up) include link to jQuery only if needed

Bug 9618: (follow-up) include link to jQuery only if needed

The jQuery lib is useful only if js code is filled into the
intranetuserjs pref.

Signed-off-by: Campbell Reid-Tait <campbellreidtait@gmail.com>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
To test:
- Use Quick spine label creator
- Make sure you have Javascript in your intranetuserjs system
  preference
- Validate Javascript effect on screen or check source code
  to make sure your code is visible there.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 94868f61c4c395f8393d34862a99609247f6dd73)
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>