Add travis (the doc key is incorrect).
diff --git a/.travis.yml b/.travis.yml
new file mode 100644
index 0000000..c9371be
--- /dev/null
+++ b/.travis.yml
@@ -0,0 +1,19 @@
+language: rust
+sudo: false
+script:
+  - cargo build --verbose
+  - cargo test --verbose
+  - cargo doc
+after_success: |
+  [ $TRAVIS_BRANCH = master ] &&
+  [ $TRAVIS_PULL_REQUEST = false ] &&
+  echo '<meta http-equiv=refresh content=0;url=rand/index.html>' > target/doc/index.html &&
+  pip install ghp-import --user $USER &&
+  $HOME/.local/bin/ghp-import -n target/doc &&
+  git push -qf https://${TOKEN}@github.com/${TRAVIS_REPO_SLUG}.git gh-pages
+env:
+  global:
+    secure: bNUxFmA5uEdKKdVDtgb+5WQuMRDZ6QxK5152sIZWSimxyr/x5erNZ1uacPh02Ng92dbUQ66wz90WPmqTwoL0EeJ/FmZDd29hRHXe82MNpz47QX3cGMgFNldQ2GmJmCHBXKu373B80o/ZB+BTVcYcl1ksTXuIhQg2wZtXh8bZ9F4=
+notifications:
+  email:
+    on_success: never