- Take also childrens' childrens into account when setting hasAppliedChildren for hierarchical facets so that the facets are properly opened also for levels deeper than 2.

- see docs at https://developers.exlibrisgroup.com/primo/apis/webservices/xservices/search/briefsearch.

Fixed the indentation of a couple of member variable declarations.

Fixed the character encoding of Voyager purchase history lines.

- Make translate() optionally accept an array of domain and string
- Fix hierarchical facet display text handling to translate the result when required.
- Added test coverage

Make sure string is a string in the constructor of TranslatableString…

Make sure string is a string in the constructor of TranslatableString since it could also be a TranslatableString object and that would break __toString().

The footer tag does not need a role.

NOTE: The right way to use ARIA's search role when inside a form is still in discussion, anyway I
changed in a way that both works AND gets validated by W3C.

More Info on:
https://github.com/w3c/wcag/issues/113

The logo role doesn't exist.

Notes:
https://awkawk.github.io/using_nav.html
http://www.w3.org/WAI/GL/wiki/Using_HTML5_nav_element#Example:The_.3Cnav.3E_element

The header tag does not need a role attribute.

In the previous pull request I had to change location of the role, but since then the master
branch removed the wrong located search role, thus making this commit an "adder" rather than a
"changer".

This will prevent VuFind from generating an empty h4 tag.

Improved the SystemStatus AJAX call to also set HTTP status codes acc…