Update travis to use Rust 1.30

Author: killercup

.travis.yml

@@ -6,11 +6,11 @@ rust:
 
 matrix:
   include:
-  - rust: 1.29.1
+  - rust: 1.30.1
     env: CLIPPY=YESPLEASE
     before_script: rustup component add clippy-preview
     script: cargo clippy --all-targets --all -- -D warnings
-  - rust: 1.29.1
+  - rust: 1.30.1
     env: RUSTFMT=YESPLEASE
     before_script: rustup component add rustfmt-preview
     script: cargo fmt --all -- --check