#1380 Add a user preference to suppress translations on title pages

[Ahasuerus]

Create a new user preference to suppress translations on title pages. Change the wording of the currently existing user preference from "Display translations" to "Display translations on Author and Series pages".

[Ahasuerus]

Implemented in:

biblio/mypreferences.py
biblio/submitpreferences.py
biblio/title.py
common/SQLparsing.py
common/login.py
scripts/add_display_title_translations.sql

Installed in SVN 584 on 2020-12-29. Closing the FR.