Get rid of travis

.travis.yml

@@ -1,44 +0,0 @@
-language: cpp
-dist: focal
-os: linux
-jobs:
-  include:
-  - env: TARGET=release_linux-amd64-librw_gl3_glfw-oal
-    os: linux
-  - env: TARGET=debug_linux-amd64-librw_gl3_glfw-oal
-    os: linux
-  - env: TARGET=release_macosx-amd64-librw_gl3_glfw-oal PREMAKE5=premake-5.0.0-alpha15
-    compiler: clang
-    os: osx
-    osx_image: xcode12u
-  - env: TARGET=debug_macosx-amd64-librw_gl3_glfw-oal PREMAKE5=premake-5.0.0-alpha15
-    compiler: clang
-    os: osx
-    osx_image: xcode12u
-addons:
-  apt:
-    update: true
-    packages:
-      - linux-libc-dev
-      - libopenal-dev
-      - libglew-dev
-      - libglfw3-dev
-      - libsndfile1-dev
-      - libmpg123-dev
-      - gcc-8-multilib
-      - g++-8-multilib
-  homebrew:
-    packages:
-      - libsndfile
-      - mpg123
-      - glew
-      - glfw
-      - openal-soft
-script:
-  - mkdir -p "$TRAVIS_BUILD_DIR/build"
-  - cd "$TRAVIS_BUILD_DIR"
-  - if [ "$TRAVIS_OS_NAME" = linux ]; then ./premake5Linux --with-librw gmake2; fi
-  - if [ "$TRAVIS_OS_NAME" = osx ]; then curl -L -o "${PREMAKE5}.zip" "https://github.com/premake/premake-core/releases/download/v5.0.0-alpha15/${PREMAKE5}-src.zip" && unzip -q "${PREMAKE5}.zip" && cd "$PREMAKE5" && make -f Bootstrap.mak osx && cd .. && "./${PREMAKE5}/bin/release/premake5" --with-librw gmake2; fi
-  - cd build
-  - if [ "$TRAVIS_OS_NAME" = linux ]; then env CC=gcc-8 CXX=g++-8 make config=$TARGET -j4 verbose=1; fi
-  - if [ "$TRAVIS_OS_NAME" = osx ]; then make config=$TARGET -j4 verbose=1; fi