Add support for not_ settings when dealing with any list based setting
Change isort config to explicitly parse __init__.py
Remove uneeded print statement
Only add imports if file contents exists
Add force add capability to handle case where users want to force adds to take place even for currently empty files
Make force-adds flag operational
Add test to assert force_adds flag works as expected
Fix isort to match text expectations for force_add
Merge pull request #147 from timothycrosley/feature/fix-issue-139

Feature/fix issue 139