Delete trailing whitespace
Remove unused imports
Reformat imports to use multiple lines
Reorder imports as recommended by PEP8
Reformat docstrings as recommended by PEP257
Remove redundant if/else
Add line breaks to long lines
Remove unused variable
Use is operator when comparing against None
Use single quotes for strings
Convert unassigned list comprehension to loop
Merge pull request #37 from jcollado/blitzdb-backends-file-backend-cleanup

blitzdb.backends.file.backend cleanup