Replace common module with validate module. Move validation function from feed module to validate module and remove feed.py. Correct any usage of validation functions from common and feed modules into validate module.
Patch by: Pawel Solyga
Review by: to-be-reviewed
"""Error types for dispatcher mechanism
"""
class DispatcherError(Exception):
"""Base class for all Dispatcher errors"""
class DispatcherKeyError(KeyError, DispatcherError):
"""Error raised when unknown (sender,signal) set specified"""
class DispatcherTypeError(TypeError, DispatcherError):
"""Error raised when inappropriate signal-type specified (None)"""