Update nightly Rust version to keep in sync with Servo.

frewsxcv · frewsxcv · commit be0e08e1e354 · 2016-03-20T21:46:27.000-04:00
Rustup happened in servo/servo#10076
diff --git a/.travis.yml b/.travis.yml
@@ -4,7 +4,7 @@ os:
   - osx
 rust:
   - nightly
-  - nightly-2016-03-07 # Should be kept in sync with Servo.
+  - nightly-2016-03-18 # Should be kept in sync with Servo.
 matrix:
   allow_failures:
     - rust: nightly
