Merge pull request #510 from gossi/master

Add DataFetcherInterface for generated Map Classes. Fixes #508
fix array casting in InCriterion and InModelCriterion. Fix #492
Merge pull request #512 from lunika/InCriterionFix

fix array casting in InCriterion and InModelCriterion. Fix #492
Install Behaviors with Composer
Refactoring + Error Messages

Error Messages:
- when composer.json lacks required information
- when a Behavior is not an instance of \Propel\Generator\Model\Behavior

New build option: —composer-dir to locate the directory where
composer.json and composer.lock reside

Use the Propel ServiceContainer to store the ComposerFinder (instead of
Singleton)