Avoid pastescript for config file parsing

[mvdbeek]

No description provided.

[nsoranzo]

Is this because of missing pkg_resources (i.e. setuptools not installed by default)?

It seems that's the only use of pulsar.util.pastescript, we can remove the module. I can push a commit to do so, if you like.

[mvdbeek]

I think we need pastescript to serve the wsgi app via paste ?

[mvdbeek]

(this should obviously also be modernized or removed)

[nsoranzo]

I think we need pastescript to serve the wsgi app via paste ?

I pushed the changes here, and tests pass.
pulsar[web] has Paste and PasteScript as extra dependencies, so I suppose that's why.