Expand functionality of /latest

[noccor]

If we want to refer to the latest version of documentation we can use /latest like so:

https://gemdocs.org/gems/appsignal/latest

However if we want to link to a specific page in the latest version of the documentation, this is not currently possible. It would be really useful if we could use something like:

https://gemdocs.org/gems/appsignal/latest/Appsignal/Transaction.html

or, how rubydoc did it:

https://gemdocs.org/gems/appsignal/Appsignal/Transaction.html

to link to the specific page, in the latest version of a repo's documentation.

[adam12]

Thanks for the feedback. Let me look into adding this.