Revert "Attempt to allow travis to fail on nightly"

This reverts commit 8e819ad628.

.travis.yml

@@ -1,33 +1,30 @@
 language: rust
-rust:
 matrix:
   include:
-    - rust: stable
-      env: FEATURES=
-    - rust: stable
-      env: FEATURES=--no-default-features
-    - rust: beta
-      env: FEATURES=
-    - rust: beta
-      env: FEATURES=--no-default-features
-    - rust: nightly
-      env: FEATURES=--features=bench
-    - rust: nightly
-      env: FEATURES=--features=simd,bench
-    - rust: nightly
-      env: FEATURES=--features=simd_opt,bench
-    - rust: nightly
-      env: FEATURES=--features=simd_asm,bench
-    - rust: nightly
-      env: 'FEATURES="--no-default-features --features=bench"'
-    - rust: nightly
-      env: 'FEATURES="--no-default-features --features=simd,bench"'
-    - rust: nightly
-      env: 'FEATURES="--no-default-features --features=simd_opt,bench"'
-    - rust: nightly
-      env: 'FEATURES="--no-default-features --features=simd_asm,bench"'
-  allow_failures:
-    - rust: nightly
+  - rust: stable
+    env: FEATURES=
+  - rust: stable
+    env: FEATURES=--no-default-features
+  - rust: beta
+    env: FEATURES=
+  - rust: beta
+    env: FEATURES=--no-default-features
+  - rust: nightly
+    env: FEATURES=--features=bench
+  - rust: nightly
+    env: FEATURES=--features=simd,bench
+  - rust: nightly
+    env: FEATURES=--features=simd_opt,bench
+  - rust: nightly
+    env: FEATURES=--features=simd_asm,bench
+  - rust: nightly
+    env: 'FEATURES="--no-default-features --features=bench"'
+  - rust: nightly
+    env: 'FEATURES="--no-default-features --features=simd,bench"'
+  - rust: nightly
+    env: 'FEATURES="--no-default-features --features=simd_opt,bench"'
+  - rust: nightly
+    env: 'FEATURES="--no-default-features --features=simd_asm,bench"'
 script:
   - cargo build --verbose $FEATURES
   - cargo test --verbose $FEATURES