added Haskell version of RENDLER

still a bit incomplete, don't merge yet.
After `cabal-update`:

```
vagrant@mesos:haskell (wip-haskell-drexin) $ cabal install
Resolving dependencies...
cabal: Could not resolve dependencies:
trying: rendler-0.1.0
rejecting: base-4.6.0.1/installed-8aa... (conflict: rendler => base>=4.7.0.0)
rejecting: base-4.7.0.1, 4.7.0.0, 4.6.0.1, 4.6.0.0, 4.5.1.0, 4.5.0.0, 4.4.1.0,
4.4.0.0, 4.3.1.0, 4.3.0.0, 4.2.0.2, 4.2.0.1, 4.2.0.0, 4.1.0.0, 4.0.0.0,
3.0.3.2, 3.0.3.1 (global constraint requires installed instance)
```