Database download

[boshek]

From the review:

One issue I encountered was the database download, with personal handling of the database path, is awkward. It seems that much of the work of downloading the database, and then storing the path could be automated. The storage location could be supported by the rappdirs package. There are existing examples of such file downloading and use, such as getlandsat, hydrolinks, and LAGOS to name a few with various implementations. This would make it easier for users to quickly get started using the data and eliminate the need to muck around in the Renviron file.

Other review:

The example:
file.edit("~/.Renviron")
That path does not automatically work for Windows users I think. You might want to clarify that you will probably want a .Renviron file in the same directory as your RStudio project (assuming you use RStudio)...or something like that

[boshek]

The approach I think here is to use rappdirs and then have here:

https://github.com/bcgov/tidyhydat/blob/dea7c3e3be4755437be93fbc33cb6dc992d17efe/R/download.R#L448-L452

download_hydat() out to the result of rappdirs::user_log_dir(). Then rather than call Sys.getenv("hydat_path") for hydat_path=NULL then we use rappdirs::user_log_dir().

[boshek]

Also another "are you sure" question when downloading hydat.