Merge pull request #13 from jhofmann/master

Refactoring
fix for no config file
revert backup_extensions change
3 space indents
Merge pull request #14 from stangelandcl/master

Fix for having no config file
Fixes a problem with weekly backups not being kept

This fix was suggested by tylercollier in his bug report:
https://github.com/adamfeuer/rotate-backups/issues/15
Merge pull request #16 from jhofmann/weekday-fix

Fixes a problem with weekly backups not being kept