Make travis test with all features enabled

Author: Xaeroxe

.travis.yml

@@ -5,9 +5,9 @@ rust:
   - stable
 script: |
   cargo build --verbose &&
-  cargo build --features=heapsizeof --verbose &&
+  cargo build --all-features --verbose &&
   cargo test --verbose &&
-  cargo test --features=heapsizeof --verbose &&
+  cargo test --all-features --verbose &&
   ([ $TRAVIS_RUST_VERSION != nightly ] || cargo test --verbose --no-default-features) &&
   ([ $TRAVIS_RUST_VERSION != nightly ] || cargo bench --verbose bench)
 notifications: