Test more compiler feature combinations in CI

.travis.yml

@@ -13,6 +13,12 @@ addons:
 
 # Main build
 script:
+  # Default features configuration
 - cargo build --verbose --all
+
+  # Other feature combinations 
 - cargo build --no-default-features --verbose --all
+- cargo build --features no-color --verbose --all
+
+  # Tests
 - cargo test --verbose --all