#908964 alex_b: Break out scheduler. Note: Features depends on Job Scheduler module now: http://drupal.org/project/job_scheduler .

  language, user properties from parent feed node. Note: Signatures of
  FeedsProcessor::map(), existingItemId(), FeedsParser::getSourceElement()
  changed.

Use existing() for ensuring that the importer in question actually exists in DB or in code. Plus one minor cleanup in switch statement.

Add existing() method that allows for making sure that a configurable actually exists when executing a method on it.
Usage:
try {
  ->existing()->action();
} catch(FeedsNotExistingException ) {}

Fix notices from setConfig() by making sure that all default values are present.

Add sourceSave() and sourceDelete() methods notifying plugin implementers of a source being saved or deleted. Minor cleanup on sourceForm().