[pdal] PDAL Python3 issues

[Howard Butler]

> On Jan 23, 2017, at 11:53 AM, Sebastiaan Couwenberg <sebastic at xs4all.nl> wrote:
> 
> If python-pdal can only work with the same Python version as
> libpdal-plang was built with, we'll need to drop the python3-pdal
> package or add a libpdal-plang3 for it.

This is a true statement. plang and PDAL Python extension should not use mixed Python runtimes. There is a check in setup.py that attempts to prevent it.

Howard