Support local-only projects
Render src filepath correctly without quotes
Merge branch 'master' into feature-local-only
Allow specifying the location of the source code
Update usage
Support all VCS that have a nix-prefetch script

We now use the various nix-prefetch-* scripts to fetch the source. This
makes it easy to add new sources, and also makes the code simpler.

A side effect is that we now generate a `fetchurl` source for hackage
packages, using the `hackage` mirror.

This depends on NixOS/nixpkgs#3038 and NixOS/nixpkgs#3039
Don't generate fetchurl for hackage packages
Merge branch 'master' into feature-local-only

Conflicts:
	src/Cabal2Nix/Hackage.hs
	src/cabal2nix.hs
Add zip fetcher
add Distribution.NixOS.Fetch to doctest libs
add missing extension pragma (needed for doctest)
update release.nix
hackage4nix.hs: don't re-generate broken packages
hackage4nix.hs: change the logic of 'updateNixPkgs' so that all packages
have been discovered before the re-generation process starts.
hackage4nix: disable Hydra builds for all "old" Haskell packages

Old means that we have a newer version in Nixpkgs already. If there is a reason
for the old package to still exist, i.e. because some other package is still
referring to it, then Hydra will still build the package as a dependency, but
we won't want to build old packages on their own right.
Pretty-print the meta.maintainer section as

  maintainers = with self.stdenv.lib.maintainers; [ foo ];

to make maintainer lists with multiple entries less verbose.
release.nix: run official Hydra builds with the latest GHC only
lapack in extra-libs refers to liblapack (hmatrix)
hmatrix no longer itself depends on gsl
Merge pull request #74 from Fuuzetsu/hmatrix-libs

lapack in extra-libs refers to liblapack (hmatrix)