4499b294 Follow GHC changes
8fd68186 Add ways to build hadrian using nix
e5c7a29c Do not depend on the in-tree filepath library
9dd7ad2a Fix dependencies
49718439 Bring mtl dependency back
6c5f5c9b Minor clean up of Hadrian dependencies
9aff81d4 Fix Windows build
fa95caa8 Unbreak `cabal new-build`

git-subtree-dir: hadrian
git-subtree-split: 4499b294

git-subtree-dir: hadrian
git-subtree-split: 438dc576

Addresses Issue #428

This avoids using colors when the output is, e.g., redirected to a
file. This requried a change to avoid passing the `--colour` flag to
shake (so that hadrian is in charge of colors).
Signed-off-by: Michal Terepeta <michal.terepeta@gmail.com>

- Move all .travis/*.sh functionality directly into .travis.yml
- Install Alex/Happy from PPA instead of compiling them by hand
- Skip Shake progress indicators, as they're rather useless
  on clean-slate Travis builds, and clutter up the log
- Don't use a Cabal sandbox for building so Travis can share
  $HOME/.cabal
- boot/configure only after the Shake build system is in place,
  otherwise some required *.in files are not converted, and
  Shake fails