Error when building from git

[Emmanuelle Gouillart]

Hi,

> The float16 data-type was introduced in NumPy 1.6, and while we
> currently list NumPy 1.4 as a dependency, but we're going to have to
> up that to 1.6 (I think some of it is being used in the data type
> conversion code now, e.g.).  I hope this isn't too much of an
> inconvenience!

isn't it possible to test which version of numpy is used, and remove
float16 from the list if numpy.__version__ < 1.6? It looks like a small
cost in order to be be able to support numpy 1.5. I can do the change if
there is no opposition to this.

The same thing that happened to Guillaume also happened to me as I was
rebuilding skimage 10 minutes ago, since I'm using the version of numpy
packaged by the most recent Ubuntu which is 1.5.

As I see things, it would be great if people could use skimage with the
dependencies provided by a recent version of Ubuntu, say the most recent
LTS, or the latest release of Ubuntu. We will lose many users if they
have to install a new numpy (which also means that they will have to
install non-packaged matplolib, and scipy). If you disagree with this
philosophy, please tell me :-).

My 2 cents,
Emmanuelle