New comment by tornaria on void-packages repository

https://github.com/void-linux/void-packages/pull/32641#issuecomment-904980981

Comment:
> I'm also considering adding packages `pari-elldata-small` and `pari-galpol-small` with small versions of the databases that should be good for testing and small computations.

RFC on `*-small` packages: is it worth it?

What I propose is that for the larger databases (elldata, galpol, seadata) we have a small subset that is good for moderate sizes, and enough for testing. As an example:

 - pari-elldata: full database for conductors up to 500k is 57M installed size. A reasonable small subset is conductors up to 20k which would take 1.8M of installed size.
 - pari-galpol: full database for group orders up to 143 is 73M installed size. The subset for orders up to 64 would take 12M installed size.
 - pari-seadata: normal database for primes up to 750 bits is 19M. The small database for primes up to 350 bits would be 668K. In this case there's also a "-big" version for primes up to 1100 bits which takes about 120M installed size.

The `pari-seadata-small` is suggested by upstream and it's already in this PR. The other two are easy to do.

The complete installation of pari with small databases would shrink from ~175M to ~40M of installed size (right now this is ~300M, we already save ~125M just by installing gzipped files which pari reads fine).

All databases would be incremental, e.g. `pari-elldata-small` installs small subset, `pari-elldata` contains the rest and depends on `pari-elldata-small`, etc. so this makes no difference for existing installations.

@motorto @dkwo: what do you think?