Add list of system packages required for source build.
Extract tar bundles after downloading.

Also skip tar file download if already present.
Back to building PyCifRW from mercurial source repository.

The repository builds if noweb is installed.
Rename pth file to make it include the release version.
Use new hard-linked tree instead of moving the files.
Do not install cctbx scripts.
added Portfile for diffpy.utils
ignore PortIndex files
Add the science category.

Fix code alignment as in the zope Portfile.
Require setuptools for installation.

Added depends_build as per example in py-zope-app-module Portfile.
The namespace in diffpy package is still not handled correctly.
This might have something to do with setuptools upgrade.
add 00-clean.zsh