Turbogears2 migration: preparatory changes to Pylons-based Kallithea

[Thomas De Schampheleire]

All,

I sent out a few changes for review at:
https://kallithea-scm.org/repos/kallithea/pull-request/60/_/Turbogears2_migration_preparatory_commits

These commits are originating from the tg2 branch, and can already be
applied on current Pylons-based Kallithea. Goal of this delivery is to
make the 'real' Turbogears2 migration a smaller, more clear diff.

Turbogears2 migration: replace pylons.url by kallithea.lib.utils.url
Turbogears2 migration: use sqlalchemy.url iso sqlalchemy.db1.url
Turbogears2 migration: remove some references to Pylons in comments

Comments welcome,

Thomas