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
# This dictionary maps Field objects to their associated PostgreSQL column
# types, as strings. Column-type strings can contain format strings; they'll
# be interpolated against the values of Field.__dict__ before being output.
# If a column type is set to None, it won't be included in the output.
DATA_TYPES = {
'AutoField': 'serial',
'BooleanField': 'boolean',
'CharField': 'varchar(%(max_length)s)',
'CommaSeparatedIntegerField': 'varchar(%(max_length)s)',
'DateField': 'date',
'DateTimeField': 'timestamp with time zone',
'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)',
'FileField': 'varchar(%(max_length)s)',
'FilePathField': 'varchar(%(max_length)s)',
'FloatField': 'double precision',
'ImageField': 'varchar(%(max_length)s)',
'IntegerField': 'integer',
'IPAddressField': 'inet',
'NullBooleanField': 'boolean',
'OneToOneField': 'integer',
'PhoneNumberField': 'varchar(20)',
'PositiveIntegerField': 'integer CHECK ("%(column)s" >= 0)',
'PositiveSmallIntegerField': 'smallint CHECK ("%(column)s" >= 0)',
'SlugField': 'varchar(%(max_length)s)',
'SmallIntegerField': 'smallint',
'TextField': 'text',
'TimeField': 'time',
'USStateField': 'varchar(2)',
}