[pdal] compile pdal with Python support

[Howard Butler]

> On Nov 30, 2015, at 9:12 AM, Luca Delucchi <lucadeluge at gmail.com> wrote:
> 
> Hi everybody,

Luca,

These are two separate issues:

> we are trying to compile pdal with Python support but we are not able,
> we active Python with PDAL_HAVE_PYTHON=ON but at the end of
> compilation we have no python directory.

Presumably this issue is caused by not having python-devel and numpy-devel packages installed. The cmake numpy detection is not so verbose.


> We also try to run "python setup.py build" into python directory but
> we got an error "no module packaging.version"

You must use pip or easy_install to install the packaging package:

$ pip install packaging

as a prerequisite before the PDAL Python extension can build/install.

Then the following command should work:

$ python setup.py build; python setup.py install