remove old travis file which hasn't worked for a long time

.travis.yml

@@ -1,49 +0,0 @@
-
-language: haskell
-dist: bionic
-
-addons:
-  apt:
-    sources:
-    - deadsnakes
-    - sourceline: 'ppa:hvr/ghc'
-
-git:
-  depth: 5
-
-cache:
- directories:
- - $HOME/.cabal/packages
- - $HOME/.cabal/store
- - $HOME/.cabal/bin
-
-branches:
-  only:
-  - master
-  - travis_stuff
-
-cabal-install:
-  - 3.2
-cabal:
-  - 3.2
-
-ghc:
-  - 8.10.1
-  - 8.8.3
-  - 8.6.5
-  - 8.4.4
-
-install:
-  - ghc --version
-  - cabal --version
-  - cabal update
-  - cabal check
-  - cabal outdated
-  - cabal build --enable-tests --enable-benchmarks -fparserexe
-
-script:
-  - cabal run test:Tests -- --hide-successes --ansi-tricks=false
-
-
-# todo: add making the website, this is good to check the entire set
-# of deps to be able to do this