Remove travis CI

.travis.yml

@@ -1,25 +0,0 @@
-language: "rust"
-cache: "cargo"
-rust:
-  - 1.40.0
-  - stable
-  - beta
-  - nightly
-jobs:
-  allow_failures:
-    - rust: nightly
-  fast_finish: true
-
-before_script:
-  - rustup component add rustfmt
-  - rustup component add clippy
-  - cargo generate-lockfile
-script:
-  - cargo fmt -- --check
-  - |
-      if [ "$TRAVIS_RUST_VERSION" != "1.39.0" ]; then
-        cargo clippy --all-targets --all-features -- -D warnings
-      fi
-  - cargo build --verbose
-  - cargo test --verbose
-if: "type != push OR (tag IS blank AND branch = master)"