Add `README.md` and `.travis.yml` script

This enables testing (or rather testing the packages builds) for all
released GHC versions this package is expected to work with.

Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

.travis.yml

+env:
+ - GHCVER=7.2.2
+ - GHCVER=7.4.1
+ - GHCVER=7.4.2
+ - GHCVER=7.6.1
+ - GHCVER=7.6.2
+ - GHCVER=7.6.3
+
+before_install:
+ - sudo add-apt-repository -y ppa:hvr/ghc
+ - sudo apt-get update
+ - sudo apt-get install cabal-install-1.18 ghc-$GHCVER autoconf
+ - export PATH=/opt/ghc/$GHCVER/bin:$PATH
+
+install:
+ - cabal-1.18 update
+ - ghc --version
+
+script:
+ - autoreconf -i
+ - cabal-1.18 configure -v2
+ - cabal-1.18 build
+ - cabal-1.18 check
+ - cabal-1.18 sdist

README.md

+The `hpc` Package  [![Build Status](https://travis-ci.org/ghc/packages-hpc.png?branch=master)](https://travis-ci.org/ghc/packages-hpc)
+=================
+
+See [`hpc` on Hackage](http://hackage.haskell.org/package/hpc) for
+more information.