Auto merge of #95 - debris:bump_rust_travis_version, r=jdm

Bump rust version used by travis to 1.11

If there is no reason to keep backwards compatibility with `rust 1.8.0`, let's bump *.travis.yml* to `rust 1.9.0`.

Hopefully it will help with travis build issue described in travis-ci/travis-ci#9128

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Author: bors-servo

.travis.yml

@@ -1,6 +1,6 @@
 language: rust
 rust:
- - 1.8.0
+ - 1.11.0
  - nightly
  - beta
  - stable