make data and package citation easier and more obvious

[e-kotov]

I guess not many R users know (or remember) about the citation() function, and especially about the rather awkward print(citation(<citation>), bibtex=TRUE) (quite a 'mouthful`... isn't it?)

Shall we make a simple wrapper for the citation so that it is visible in the autocomplete, in the package docs and the reference on the website?

It could be just spod_cite() that calls:

print(citation("spanishoddata"), bibtex=TRUE)

and prints it to console.

As we are also trying to urge the users to cite the data consistently, this may be a good idea.

@Robinlovelace, @eugenividal, what do you think, is it overkill?

[Robinlovelace]

No objections, it can help highlight the citation.

[eugenividal]

Sounds good