Changes to documentation as a result of review

[potterzot]

These changes primarily address some minor issues around the reporter, partner, and partner_2 parameters in ct_get_data(). It looks like in the process of implementing the convenience value of all, some documentation was not updated to reflect that defaults in some cases are now World, that all is an option, and that All is not a valid option.

[datapumpernickel]

This is a bit tricky and I can see how it can be misunderstood! I would like to work with you on how I could make this more explicit.

What you did, was this:

comtradr::ct_get_data(reporter = "DEU", 
                      start_date = 2020, 
                      end_date = 2020)

You left the argument without any specification and it goes to the default of world (as specified in the help file, whihc says: 'Partner ISO3 code(s) or NULL. See comtradr::country_codes for possible values. Default: 'World' (all partners as an aggregate).'

However what I MEANT, when I wrote setting it to NULL, was:

``` r
comtradr::ct_get_data(reporter = "DEU", 
                      partner = NULL, 
                      start_date = 2020, 
                      end_date = 2020)

Then, it will actually query all possible values.

I am not saying that you are wrong, but the way you have put it here, also is not correct, because using NULL will actually query all parameters. Not sure how to make the distinction between NULL and just not specifying the argument.

Do you have a suggestion?

[datapumpernickel]

Hi @potterzot

Thank you so much for this thorough review, your time and the helpful comments!
I will make an issue with the requested changes and will later this week comment in the thread. But since the pull request is already here and overall helpful, I thought I could include it already, but there seems to be a misunderstanding with setting the argument to NULL and leaving it in blank. I have left a comment in the respective part ofthe code!

Looking forward to your input on this!

Thanks again!