Filter section UX/UI

[tmheunis]

1. Instead of 'Filter by' wording in the placeholder text for 'filter by dataset or author name' and 'filter by keyword', consider using a filter icon instead and remove 'filter by' words.
2. Consider renaming order by 'Name' to order by 'Dataset', and then in the placeholder text remove the word 'name', so that the placeholder text reads 'Dataset or author' with filter icon.
3. Considering adding a select icon to the 'keywords' button, and also rather making it a scroll dropdown when clicking on it.
4. It would be helpful to include a filter reset button.
5. If filtering returns no results that should be clearly indicated, e.g. "No search results found."
6. When there are 4 or less subdatasets, the filtering function is not active, so the keyword tags should not appear clickable then.