add ci

.travis.yml

@@ -0,0 +1,20 @@
+language: rust
+
+install:
+  - bash ci/install.sh
+
+script:
+  - bash ci/script.sh
+
+after_success:
+  - bash ci/after-success.sh
+
+branches:
+  only:
+    - master
+    - staging
+    - trying
+
+notifications:
+  email:
+    on_success: never

ci/after-success.sh

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+set -euxo pipefail
+
+main() {
+    mkdir ghp-import
+    curl -Ls https://github.com/davisp/ghp-import/archive/master.tar.gz |
+        tar --strip-components 1 -C ghp-import -xz
+
+    ./ghp-import/ghp_import.py book
+
+    # NOTE(+x) don't print $GH_TOKEN to the console!
+    set +x
+    git push -fq https://$GH_TOKEN@github.com/$TRAVIS_REPO_SLUG.git gh-pages && echo OK
+}
+
+if [ $TRAVIS_BRANCH = master ] && [ $TRAVIS_PULL_REQUEST = false ]; then
+    main
+fi

ci/install.sh

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+set -euxo pipefail
+
+main() {
+    local tag=$(git ls-remote --tags --refs --exit-code https://github.com/rust-lang-nursery/mdbook \
+                    | cut -d/ -f3 \
+                    | grep -E '^v[0.1.0-9.]+$' \
+                    | sort --version-sort \
+                    | tail -n1)
+    curl -LSfs https://japaric.github.io/trust/install.sh | \
+        sh -s -- --git rust-lang-nursery/mdbook --tag $tag
+
+    pip install linkchecker --user
+}
+
+main

ci/script.sh

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+set -euxo pipefail
+
+main() {
+    mdbook build
+
+    linkchecker book
+}
+
+main