Merge pull request #1059 from rust-lang-nursery/db-fix-travis-yaml

Remove hyphen

Author: Diggsey

.travis.yml

@@ -104,7 +104,7 @@ matrix:
 cache:
   # We're going to download things we don't necessarily want to cache into the `target` directory, so
   # don't use travis's native `cargo` caching, which just grabs the whole folder.
-  - directories:
+  directories:
     - target/$TARGET/openssl/openssl-install
     - target/$TARGET/release
     - target/release/deps