Bug 35110: Authorities editor with JS error when only one tab

Bug 35110: Authorities editor with JS error when only one tab

Exactly like Bug 34251 for biblios :
When using the an authorities framework with all fields in the same tab, there is thrown a JS error in selectTab( "#tab0XX_panel" );
This is because no nav tabs are build in authorities/authorities.tt as BIG_LOOP has a length(size) of 1

Test plan :
1) Edit an authority framework, for example 'Meeting Name', to set all sufields in tab 0
   You may use SQL : UPDATE auth_subfield_structure SET tab=0 WHERE authtypecode='MEETI_NAME'
   Don't forget to restart memcached
2) Go to 'Authorities'
3) Click on 'New authority' then 'Meeting Name'
4) Check you don't see any JavaScript error
5) Check you can save

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Bug 35110: (follow-up) Fix comment in addbiblio.tt

Change comment in addbiblio.tt since any biblio framework may use only
one tab.
Also fixes indenting using 4 spaces.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Edit: squashed because follow-up fixes code introduced by the same
author.

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>