Remove the travis-ci configuration file

.travis.yml

@@ -1,37 +0,0 @@
-language: rust
-
-rust:
-    - "1.42.0"
-    - "1.43.1"
-    - "1.44.1"
-    - "1.45.2"
-    - "1.46.0"
-    - "1.47.0"
-    - "1.48.0"
-    - "1.49.0"
-    - "1.50.0"
-    - "1.51.0"
-    - "1.52.1"
-    - "stable"
-    - "beta"
-    - "nightly"
-
-jobs:
-    allow_failures:
-        - rust: "nightly"
-    include:
-        - name: Run cargo audit
-          rust: stable
-          env: TASK=audit
-    fast_finish: true
-
-install:
-    - cargo build --verbose
-    - if [ "$TASK" = "audit" ]; then cargo install cargo-audit; fi
-
-script:
-    - if [ "$TASK" = "audit" ]; then
-          cargo audit;
-      else
-          cargo test --verbose;
-      fi