Update rust nightly to keep in sync with Servo.

jdm · jdm · commit ec34dbf37d18 · 2016-03-20T22:03:55.000-04:00
Rustup happened in servo/servo#10076
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,7 @@
 language: rust
 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
