Related #4196

This is an honest 1, for once.
This is solved by adding this extra pretty-faces mapping:

   <url-mapping id="dataverseslash">
        <pattern value="/dataverse/#{alias}/" />
        <view-id value="/dataverse.xhtml" />
    </url-mapping>

(this is in src/main/webapp/WEB-INF/pretty-config.xml)

@landreev cool, should we fix #4196 with prettyfaces too? That one's about a trailing parenthesis, a ")".

I don't think we should encourage people to use invalid urls. A trailing back slash kind of makes sense on the end of a url; a single mismatched parenthesis? - not really.
I feel like a better error message would be a correct solution for #4196.

Added mapping for dataverse url with trailing slash.

This now allows for the user to navigate to both /dataverse/alias and /dataverse/alias/ URL's, and both return a 200 OK status code.

There was some concern about duplicate content, but that was alleviated by @landreev who claimed his work in robots.txt will block this URL format. My assumption when I created this issue was that we would forward from one format to another, not support both.

Here is what the Google Webmaster Central Blog said on Wednesday, April 21, 2010 in the To slash or not to slash post.

If both slash and non-trailing-slash versions contain the same content and each returns 200, you can:

• Consider changing this behavior (more info below) to reduce duplicate content and improve crawl efficiency.
• Leave it as-is. Many sites have duplicate content. Our indexing process often handles this case for webmasters and users. While it’s not totally optimal behavior, it’s perfectly legitimate and a-okay. :)
• Rest assured that for your root URL specifically, http://example.com is equivalent to http://example.com/ and can’t be redirected even if you’re Chuck Norris.

Correct - I don't think duplicate indexed content is a problem in our case. Google bot will only index "/dataverse/foo" and "/dataverse/foo/" separately, if it has some way to discover both urls. I don't think it should be possible to ever get to "/dataverse/foo/" by crawling the site. Plus, our current approach is to specifically discourage the bots from crawling the site (i.e., from following the search and facets links); and instead we want to make them go straight to the pages we advertise via the sitemap. The sitemap never uses the "/dataverse/name/" notation - only "/dataverse/name".
(It was still nice to fix this issue, for the benefit of the human users)

(the only times I saw google bot try to access "/dataverse/name/" was when I specifically sent it there, via their search console)