added additional metadata fields -> difficulty, education level, status, type, version, format, keywords, requirements

Create object for metadata search query.
This object is part of the SearchInputDTO object,
which gets parsed from the JSON file sent by the
front-end.

very inefficient :-) )

layouting

Check optional metadata fields before
trying to display them.

When scrolling through the search results,
load new results when the bottom of the page
is near.

Previously, when the pages had a height
smaller than the screen's height,
the footer was displayed somewhere in the
middle of the page.

Display the footer at the bottom, with
no whitespace after it.