Add more options to rows per page selector

[fstachura]

Is your feature request related to a problem? Please describe.
Currently, the "rows per page" selector allows to select only up to 25 rows per page. This makes browsing the website somewhat inefficient, especially if one is just searching for interesting datasets.
If the user is far from the servers, each page change can take seconds to load.

Describe the solution you'd like
Add options for more rows per page (I suggest 100, 250, 500 or maybe even "all", IMO there aren't that many datasets in the database right now to justify paging this granular, just don't make it the default) to the rows-per-page selector.

Describe alternatives you've considered
It's possible to just change the "take" url parameter to desired option, but that is not very intuitive nor convenient.

Additional context

PS: Thanks for maintaining the dataset repository :)