pip install misses numpy include dirs

[jorenretel]

I just installed this library. There was a small tweak I had to make to make this possible though. When I tried to install it from PyPi using pip (pip install fabia) it gave the following error:

    fabia/_fabia.c:450:31: fatal error: numpy/arrayobject.h: No such file or directory
     #include "numpy/arrayobject.h"
                                   ^
    compilation terminated.
    error: command 'gcc' failed with exit status 1

I looked into the setup.py and saw that you recently made some changes. I replaced line 51

```python
ext_modules = [Extension("fabia._fabia", ["fabia/_fabia.c"])],

by

ext_modules = [Extension("fabia._fabia", ["fabia/_fabia.c"], include_dirs=[np.get_include()])],

I checked whether the package like this was pip installable by running python setup.py sdist and subsequently running pip install on the locally created tar.gz. I think 'include_dirs=[np.get_include()]' is still necessary.

I was using python 3.6.2 and a conda environment.

[Alro10]

Hi! I created a virtualenv for python 2.7, also you would create virtualenv for python 3.5 , 3.6 or conda. After that, use this requirements.txt file.
numpy>=1.12
scipy>=0.19
sklearn

Finally, run: pip install -r requirements.txt

This worked!