Tweak travis config

.travis.yml

@@ -1,30 +1,23 @@
 language: rust
-rust:
-  - 1.15.0
-  - stable
-  - beta
-  - nightly
-sudo: false
-before_script:
-  - pip install 'travis-cargo<0.2' --user && export PATH=$HOME/.local/bin:$PATH
+matrix:
+  include:
+    - rust: stable
+    - rust: beta
+    - rust: nightly
+    - name: "master doc to gh-pages"
+      rust: nightly
+      script:
+        - cargo doc --no-deps
+      deploy:
+        provider: script
+        script: curl -LsSf https://git.io/fhJ8n | rustc - && (cd target/doc && ../../rust_out)
+        skip_cleanup: true
+        on:
+          branch: master
 script:
   - cargo test
   - cargo test --manifest-path test-suite/Cargo.toml
   - rustdoc --test README.md -L target
-  - test "$TRAVIS_RUST_VERSION" != "1.15.0" && cargo doc --no-deps || echo "skipping cargo doc"
-after_success:
-  - travis-cargo --only nightly doc-upload
-  - travis-cargo coveralls --no-sudo
-env:
-  global:
-    secure: "IDm3Oc3bmIL4/6zixovwkuTkbinqWnKdLfeuKTtHqT4ZbVy+rxTDQBgLGfVngymjciHWkJnvQ8/2nT3/KW4MPNY9Sqt3NfWvO7vj9cXypeNeJ4xFrVK49F7CMM4KTCeSMlDKR1C0TVYGgxFIViLtBw/imivl9fk6J489eKv36sA="
-
 notifications:
   email:
     on_success: never
-addons:
-  apt:
-    packages:
-      - libcurl4-openssl-dev
-      - libelf-dev
-      - libdw-dev