update travis to run on ghc 7.0, and 7.10

.travis.yml

@@ -1,26 +1,48 @@
 env:
- - GHCVER=7.4.2
- - GHCVER=7.6.3
- - GHCVER=7.8.2
- - GHCVER=head
+ - CABALVER=1.16 GHCVER=7.0.4
+ - CABALVER=1.16 GHCVER=7.4.2
+ - CABALVER=1.18 GHCVER=7.6.3
+ - CABALVER=1.18 GHCVER=7.8.3
+ - CABALVER=1.22 GHCVER=7.10.1
+ - CABALVER=head GHCVER=head
 
 matrix:
   allow_failures:
    - env: GHCVER=head
 
 before_install:
- - sudo add-apt-repository -y ppa:hvr/ghc
- - sudo apt-get update
- - sudo apt-get install cabal-install-1.18 ghc-$GHCVER
- - export PATH=/opt/ghc/$GHCVER/bin:$PATH
+ - travis_retry sudo add-apt-repository -y ppa:hvr/ghc
+ - travis_retry sudo apt-get update
+ - travis_retry sudo apt-get install cabal-install-$CABALVER ghc-$GHCVER # see note about happy/alex
+ - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:$PATH
 
 install:
- - cabal-1.18 update
- - cabal-1.18 install --only-dependencies --enable-tests;
+ - cabal --version
+ - echo "$(ghc --version) [$(ghc --print-project-git-commit-id 2> /dev/null || echo '?')]"
+ - travis_retry cabal update
+ - if [ "${GHCVER}" = "7.0.4" ]; then
+    cabal install --only-dependencies;
+   else
+    cabal install --only-dependencies --enable-tests;
+   fi
 
 script:
- - cabal-1.18 configure --enable-tests -v2
- - cabal-1.18 build
- - cabal-1.18 test
- - cabal-1.18 check
- - cabal-1.18 sdist
+ - if [ "${GHCVER}" != "7.0.4" ]; then
+      cabal configure --enable-tests -v2;
+   else
+      cabal configure -v2;
+   fi
+ - cabal build
+ - if [ "${GHCVER}" != "7.0.4" ]; then
+       cabal test;
+   fi;
+ - cabal check
+ - cabal sdist
+ - export SRC_TGZ=$(cabal info . | awk '{print $2 ".tar.gz";exit}') ;
+   cd dist/;
+   if [ -f "$SRC_TGZ" ]; then
+      cabal install --force-reinstalls "$SRC_TGZ";
+   else
+      echo "expected '$SRC_TGZ' not found";
+      exit 1;
+   fi