fix custom manager inheritance.
change deserialization of None values
remove unused variables and imports
add isnull lookup support
remove managers patching on field initialization
add runtime managers patching via class_prepared signal
change list to iterator
fix typo
simplify comparisons and remove default value from dict.get method call
pep8, remove unused import
use currency_field_name to get field name
rename currency_field_name and move it to utils
prevent duplicate currency fields during South data migrations, fixes #34
fix
Merge pull request #35 from lionheart/master

Prevent duplicate currency fields during South data migrations
updated maintainer's data
fix setup script
Merge pull request #37 from tzenderman/master

Fix failing setup script.
Support for ExpressionNode updates:
account.balance = F('balance') + balance
Added tests for changing money using relative values ( F() )