Add travis.yml config

Author: faern

.travis.yml

@@ -0,0 +1,27 @@
+language: rust
+cache: cargo
+rust:
+  - nightly
+  - stable
+  - beta
+os:
+  - osx
+
+
+before_script:
+  - rustup component add rustfmt-preview
+  - rustfmt --version
+
+script:
+  - cargo build --verbose
+  - cargo test --verbose
+  - if [ "${TRAVIS_RUST_VERSION}" = "nightly" ]; then
+      cargo fmt -- --write-mode=diff;
+    else
+      echo "Not checking formatting on this build";
+    fi
+
+notifications:
+  email:
+    on_success: never
+    on_failure: never