Automate process of building docs for docs.rust-embedded.org

[markhildreth]

When accessing any of the three books from the docs.rust-embedded.org domain, the version of the documents received are over two months out of date, dating back to March 15th.

> date
Fri May 29 15:40:13 EDT 2020
> curl -s --head "https://rust-embedded.github.io/discovery/" | grep last-modified
last-modified: Thu, 28 May 2020 02:46:55 GMT
> curl -s --head "https://docs.rust-embedded.org/discovery/" | grep last-modified
last-modified: Sun, 15 Mar 2020 19:52:23 GMT
> curl -s --head "https://rust-embedded.github.io/book/" | grep last-modified
last-modified: Fri, 29 May 2020 17:35:25 GMT
> curl -s --head "https://docs.rust-embedded.org/book/" | grep last-modified
last-modified: Sun, 15 Mar 2020 19:52:23 GMT
> curl -s --head "https://rust-embedded.github.io/embedonomicon/" | grep last-modified
last-modified: Tue, 21 Apr 2020 17:28:25 GMT
> curl -s --head "https://docs.rust-embedded.org/embedonomicon/" | grep last-modified
last-modified: Sun, 15 Mar 2020 19:52:23 GMT

Additionally, the bookshelf is also out of date:

> curl -s --head "https://docs.rust-embedded.org" | grep last-modified
last-modified: Sun, 15 Mar 2020 19:52:23 GMT

This is because the docs.rust-embedded.org domain looks specifically to the /docs repository, which uses submodules to pull in the other book repositories. Unfortunately, there doesn't appear to be any automated system (or if there is, it is not working) to rebuild the gh-pages branch in the /docs repo enough to keep them up to date.

[adamgreig]

I believe that's because those are all generated/hosted via https://github.com/rust-embedded/docs/tree/gh-pages which has each book as a submodule. Not necessarily a great system...

[markhildreth]

@adamgreig Ah, thanks, didn't realize they were all in that repo. Is there a system in place that should be automating this that isn't working, or is there no such automatic system in place yet?

[adamgreig]

I'm not sure actually. I don't see anything that would cause a regular build to run, but such things are possible to have on Travis.

[yerke]

Fixed with rust-embedded/rust-embedded.github.io#24