Reordering

Created a library Reordering which is ment to be an alternative for Binary and Continous.
Added the example traveling_salesman.hs to demonstrate how it works.

There is administrative work to do: I couldn't manage to import and export the functions the way I wanted. Thats why the example is in the wrong directory. Sorry, but I am still learning.
Please use spaces not tabs to indent; I've mostly used two spaces for an indentation level.
Make sure your `if`s are properly aligned (I've got a bunch of compile errors on some `if` expressions).
The style used in `moo` is three-line layout: https://github.com/astanin/moo/blob/master/Moo/GeneticAlgorithm/Continuous.hs#L174

```haskell
                if norm2 rem <= 1e-6 * maximum (map norm2 exs)
                then exs -- skip this vector, as linear depenent with dir0
                else rem : exs -- add to the list of orthogonalized vectors
```