Redirect URLs without a version to the latest version

[hdgarrood]

Fixes #277

I tested this and it does include the fragment too, so e.g. if you use the URL that @garyb gave

https://pursuit.purescript.org/packages/purescript-halogen/docs/Halogen.Query#v:action

it does focus on action after redirecting to the page with the latest version. :tada:

[garyb]

Awesome, thanks!

[fiatjaf]

Is this live? Doesn't seem to work from here.

[hdgarrood]

No, if an issue is closed that just means the fix is in master. If you want to know what's live then you should compare the version at the bottom of any page on pursuit.purescript.org with the git history here