Remove .travis.yml

Former-commit-id: 2aff9523aaeaadd92b632972a9e67dcd7c2266f9
Former-commit-id: 4705e9954e897d82e6c2e04fea941c2a76f7ebdb

.travis.yml

@@ -1,15 +0,0 @@
-language: rust
-rust:
-  - stable
-  - beta
-  - nightly
-matrix:
-  allow_failures:
-    - rust: nightly
-    - rust: beta
-  fast_finish: true
-cache: cargo
-before_install:
-  - sudo apt-get update
-  - sudo apt-get -y install xorg-dev
-  - sudo apt-get -y install libsdl2-dev libsdl2-image-dev