Merge tag '3.3.1' into develop

3.3.1
Fix comment
Add test case for issue #108
Merge pull request #109 from timothycrosley/feature/fix-issue-108

Add test case for issue #108
Add another test case, including a custom configuration
Merge pull request #110 from timothycrosley/feature/fix-issue-108

Add another test case, including a custom configuration
Fix test data
Fix test
Fix issue 108: deal with imports that start with 'from' and have import statement on another line
Merge pull request #111 from timothycrosley/feature/fix-issue-108

Feature/fix issue 108
Add unit test for atomic sorting feature
Fix test for atomic
Fix issue #106 verify isort doesn't break Python scripts
Document atomic support and usage
Merge pull request #112 from timothycrosley/feature/fix-issue-106

Feature/fix issue 106
Bump version to 3.4.0
Merge branch 'release/3.4.0'