Sluggable failing tests (no. queries and regex)
Port new sluggable behavior

Fixes #371 where it reduces the number of queries to generate a
unique slug to 3, and conditionally generates the findOneBySlug
method when the slug column is not with the default name "slug".
Update AbstractFormatter.php

Clear relations of the currentObject before reuse it (see https://github.com/propelorm/Propel2/issues/599)
Merge pull request #603 from sbarex/master

Update AbstractFormatter.php
Merge pull request #376 from mhitza/fewer-slug-queries

Sluggable behavior forward port
Made Sluggable port #376 compatible with all databases
Fixed 'object' column type to allow saving the same object.
Fixed #477, Fixed #607, Fixed #604, Fixed #610