Moved rustfmt commands after build, so that it passes.

Also added clippy into CI checks, but allowing warnings to pass for now.

.travis.yml

@@ -7,8 +7,9 @@ before_install:
   - sudo chown $USER /usr/local/bin/protoc
   - sudo chown -R $USER /usr/local/include/google
 script:
-  - cargo fmt --all -- --check
   - cargo build --verbose --all
+  - cargo fmt --all -- --check
+  - cargo clippy
   - cargo test --verbose --all
 rust:
   - stable