Add status page and update warning.

[ldecicco-USGS]

Here's how it looks:

y <- readNWISqw("391259097001800", parameterCd = "00605")
Warning message:                                                                                     
WARNING: Beginning in February 2024 the NWIS qw data endpoint will not deliver new data or updates to existing data. 
Eventually the endpoint will be retired. For updated information visit:
https://waterdata.usgs.gov/nwis/qwdata
For additional details, see vignettes:
https://doi-usgs.github.io/dataRetrieval/articles/Status.html
https://doi-usgs.github.io/dataRetrieval/articles/qwdata_changes.html
If you have additional questions about the qw data service, email CompTools@usgs.gov

We can merge this PR and make sure the documentation deploys as expected. Here's how the banner looks on my screen locally:

[lstanish-usgs]

@ldecicco-USGS Updates look great! I like the new dedicated 'Status' page as well. That will make it easier to update folks about changes. I noted a few typos and minor edits to the Status page. Pending those fixes merging is approved! Thanks