add EveryBeam

[gijzelaerr]

https://git.astron.nl/RD/EveryBeam

currently, the software manually downloads beam models. Tammo-jan indicated astron wants to rewrite the code, and have some beam models without downloading. WHen this is implemented, we can add the package. WSclean can then be rebuild with support for this package.

[gijzelaerr]

Tammo-Jan indicated that this is still planned but did not happen yet.