Remove TravisCI

.travis.yml

@@ -1,25 +0,0 @@
-language: cpp
-
-os:
-  - osx
-
-osx_image: xcode11.3
-
-notifications:
-  email:
-    on_failure: change # default: always
-
-addons:
-  homebrew:
-    packages:
-      - mingw-w64
-env:
-  - MAKE_BUILD=make
-  - MAKE_BUILD=debug
-
-script:
-  - if [ $MAKE_BUILD = make ]; then make; fi
-  - if [ $MAKE_BUILD = debug ]; then make debug; fi
-
-stages:
-  - test