Remove unused travis file

.travis.yml

@@ -1,43 +0,0 @@
-language: rust
-sudo: required
-rust:
-  - beta
-  - stable
-os:
-  - linux
-  - osx
-env:
-  matrix:
-    - CI_BUILD_FEATURES="bundled"
-    - CI_BUILD_FEATURES="gfx image ttf mixer"
-  global:
-    - RUST_TEST_THREADS=1
-    - TRAVIS_CARGO_NIGHTLY_FEATURE=""
-    - LD_LIBRARY_PATH: "/usr/local/lib"
-    - secure: MJhmVnQ2IM7+sVmc3vU4ndKOcQgLLeHUPW3qaQBQHKQmvoswCwQK60N17uSgWn1Ln8teqvSRHq4KclIjdMHI+VuQXJHQKHDgjcYbHxwmc3AM1Whnp0XB44ksKUmD109BGWSfZQxzF+6dA+YNOQ+mti+bpydMu8n2FMVjA/SXwQ8=
-
-install:
-  - |
-    if [[ $CI_BUILD_FEATURES != *"bundled"* ]]; then
-      if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then
-        sudo apt-get update
-        sudo apt-get install --assume-yes libgl1-mesa-dev
-      fi
-      bash scripts/travis-install-sdl2.sh
-    fi
-
-before_script:
-  - shopt -s expand_aliases
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then alias pip=pip2; fi
-  - |
-    pip install 'travis-cargo<0.2' --user &&
-    export PATH=$HOME/.local/bin:$PATH &&
-    export PATH=~/Library/Python/2.7/bin:$PATH
-script:
-  - |
-    travis-cargo build -- --features "${CI_BUILD_FEATURES}" &&
-    travis-cargo build -- --examples --features "${CI_BUILD_FEATURES}" &&
-    travis-cargo test -- --features "${CI_BUILD_FEATURES}" &&
-    travis-cargo --only stable doc -- --features "${CI_BUILD_FEATURES}"
-after_success:
-  - travis-cargo --only stable doc-upload