process: ci: enable clippy checks as part of the build

.travis.yml

@@ -38,7 +38,12 @@ matrix:
         - cargo tarpaulin -v --forward --out Xml
         - bash <(curl -s https://codecov.io/bash)
 
+before_script:
+  - rustup component add clippy
+
 script:
+  - cargo clippy --all-targets --all-features
+  - cargo build
   - cargo test
 
 env:

appveyor.yml

@@ -7,9 +7,11 @@ install:
   - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin
   - rustc -V
   - cargo -V
+  - rustup component add clippy
 
 build: false
 
 test_script:
+  - cargo clippy
   - cargo build --target %TARGET%
   - cargo test --target %TARGET%