Merge pull request #3448 from tuncer/unused-cabal-install

No need to install cabal-install package

.travis.yml

@@ -17,7 +17,7 @@ env:
 before_install:
  - travis_retry sudo add-apt-repository -y ppa:hvr/ghc
  - travis_retry sudo apt-get update
- - travis_retry sudo apt-get install --force-yes cabal-install-1.24 ghc-$GHCVER-prof ghc-$GHCVER-dyn happy
+ - travis_retry sudo apt-get install --force-yes ghc-$GHCVER-prof ghc-$GHCVER-dyn happy
  - if [ "$TEST_OLDER" == "YES" ]; then travis_retry sudo apt-get install --force-yes ghc-7.0.4-prof ghc-7.0.4-dyn ghc-7.2.2-prof ghc-7.2.2-dyn; fi
  - export PATH=$HOME/.cabal/bin:/opt/ghc/$GHCVER/bin:/opt/cabal/1.24/bin:$PATH
  - git version