Version 0.4.0

Since last version

• Add scss-lint to dev, rewrite some part to follow the standard.
• Update the readme (typos, update documentation, add badges) (#6, #7)
• Clarify the page-break class, add page-break-before (do the same as page-break, it is an alias) (#5)
• Add license file (#9)
• Add codeclimate to the repo
• Other details (please check the commits for more details)

Note: This release should not have any breaking change