Deap

- benchmarks: fix computation of DTLZ2, DTLZ3 and DTLZ4.
- cma 1+Lambda: fix the computation of the rank-one update.
- gp: replace the generate functions default value for the argument `type_` from `object` to `None`.
This removes the obligation to define the `type_`` argument for the individual generation function when doing STGP.
- gp: fix a bug with OOGP when calling addPrimitive and addTerminal in arbitrary order.
- gp: fix Ephemeral regeneration with mutEphemeral. rev: `ae46705`.
- gp: fix issue 35 - from_string had issues with OOGP.
- Fix issue 26: in four examples, files are opened but never closed.

- tools: issue 26: Operators with bounds do not work correctly when
bounds are provided as list instead of iterator. rev: `b172432515af`, `9d4718a8cf2a`.
- tools: add missing arguments to sortLogNondominated (`k`, `first_front_only`). rev: `f60a6520b666`, `4de7df29dd0f`.
- gp: issue 32: :meth:`~deap.gp.PrimitiveTree.from_string` used incorrect argument order with STGP. rev: `58c1a0711e1f`.

- creator: Issue 23: error in creator when using unicode source.
- creator: create does not handle proper slicing of created classes inheriting
from ``numpy.ndarray`` anymore. This was bug prone and extremely hard to maintain.
Users are now requested to include ``numpy.copy()`` operation in their
operators. A tutorial on inheriting from numpy is on its way.