Host Rustdoc documentation on the project website

[dominic-mulligan-arm]

Requested feature
The Rustdoc documentation present in the code should be automatically generated and hosted somewhere accessible, e.g. the Veracruz project website.

Motivation
At the moment, we have patchy Rustdoc coverage (there's another, existing issue open to try to improve this) but no way of browsing what documentation exists easily. To do this at present, you have to first generate the documentation build manually, and then open a browser at target/doc/package_name/index.html to see the generated documentation. It would be better to just have this done automatically and the documentation hosted on the user's behalf.

Additional context
See also issue #29 which aims to add build targets for Rustdoc to the project Makefiles.