Deploy book via CI

[paulhauner]

Description

In /book there is an mdbook containing our hand-written documentation (note: this is distinct to the rust docs).

The book is presently deployed at http://lighthouse-book.sigmaprime.io/

I deployed it from my local machine (with the same credentials as the ci server) using:

aws s3 sync book/book/ s3://lighthouse-book.sigmaprime.io/ --exclude '.lock' --delete

Over at #543 I have modified the Dockerfile and gitlab-ci.yaml in an attempt to get it to deploy via gitlab CI (just like the rust docs do). I'm getting a credentials error at the moment.

The notable changes to the Dockerfile are:

• Add RUN cargo install mdbook: installs the binary crate that builds the book.
• Remove git-lfs (it's no longer required on master)

For gitlab-ci.yaml, this is what I have added. It seems to work, it just fails on credentials:

build-book:
  stage: document
  script:
    - mdbook build book
    - aws s3 sync book/book/ s3://lighthouse-book.sigmaprime.io/ --exclude '.lock' --delete
  only:
   - master

[paulhauner]

@spble I assigned you because you've been the CI-guy so far :)