Refactors language translation link settings

- Strips whitespace around language code setting so any amount of
spacing can be introduced into the settings and the app won’t silently
not configure the language code URL properly.
- Adds ability to remove all language links and the app won’t break.
Ties into #483.
- Edits language links code comments to be consistent with other
settings in the settings file and adds a space after the colon in the
settings to be consistent with Ruby style guide key/value styling.
Refactors utility areas around homepage search box

Refactors area above and below search box on homepage so that when
language links are absent the height of the utility area doesn’t
collapse. Also, renames bottom utility area to be more generic.