Auto merge of #32 - behnam:travis-features, r=mbrubeck

[travis.yml] Add build script for new `with_serde` feature

Example run: https://travis-ci.org/behnam/rust-unicode-bidi/jobs/232979295

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.travis.yml

@@ -1,9 +1,19 @@
 sudo: false
 language: rust
+
 rust:
   - nightly
   - beta
   - stable
 
+matrix:
+  fast_finish: true
+
 notifications:
   webhooks: http://build.servo.org:54856/travis
+
+script:
+  - cargo build --verbose
+  - cargo test --verbose
+  - cargo test --verbose --features with_serde
+  - cargo doc --verbose --no-deps