Add note that authenticated downloads are not supported by read_gtfs()

[philiporlando]

This spawned from #223 and documents that GTFS downloads requiring authentication are not supported by {tidytransit}.

• Adds note to README.md
• Adds note to {roxygen2} comment for read_gtfs() function
• devtools::document() was executed to update the corresponding read_gtfs.Rd file.

[mpadge]

@philiporlando I think having this in the README is a step too far. Happy for @polettif to decide, but feeds hidden behind paywalls or whatever is against the entire spirit of GTFS, as clearly indicated in the official overview:

Making a Transit feed publicly available

The simplest way to make a feed public is to host it on a web server and publish an announcement that makes it available for use.

GTFS should by definition be public. I think just removing the note from the README and leaving it as a side note in the function documentation only is fine.

[polettif]

@philiporlando I think having this in the README is a step too far. Happy for @polettif to decide, but feeds hidden behind paywalls or whatever is against the entire spirit of GTFS, as clearly indicated in the official overview:

Yes, I agree. @philiporlando Thank you for the PR, please remove the note in the README then this is ready to get merged 👍

[philiporlando]

@philiporlando I think having this in the README is a step too far. Happy for @polettif to decide, but feeds hidden behind paywalls or whatever is against the entire spirit of GTFS, as clearly indicated in the official overview:

Yes, I agree. @philiporlando Thank you for the PR, please remove the note in the README then this is ready to get merged 👍

@polettif Done!