Revert to ~> 2.1 of postfix
Use v1.1.2 of rds-s3-backups cookbook, bump to 1.2.3

Fixes a syntax error in the backup script
Use rds-s3-backup v1.1.3, bump to v1.2.4

Fixes a syntax error w/ the backup double-check.
Use v1.1.4 of rds-s3-backups cookbook, fixes logging display typo
Use current, latest, version of Berkshelf, Test Kitchen, kitchen-vagrant
Bump to 1.2.6, update CHANGELOG
Revert "Revert to ~> 2.1 of postfix"

This reverts commit 9a230e965f65cb88dfe4f9a5a06d2ceb0f709a12.

Conflicts:
	CHANGELOG.md
	metadata.rb