v0.3.0

• Merge branch 'master' of https://github.com/re-ce/rececss 494a911
• feat: add background rulesets 6d78499
• feat: add background rules 06dc17e
• docs: add examples e02b066
• build: npm ignore examples 0bbeb25
• Update README.md 6da4d38
• Merge branch 'master' of https://github.com/re-ce/rececss c5c2a19
• feat: background rulesets 6bb72b3
• Update README.md 8f697b6
• Update README.md e2e08a3
• Update README.md 4546663
• Update README.md 0ee62cb
• Update README.md 7f5ff48
• Update README.md a29c140
• Update README.md 1661b42
• Update README.md 15f36d3
• Update README.md c69ac7e
• Update README.md a2a4639
• Update README.md e1cf8a8
• Add states description 70ac2be
• Add motivation section 333e721

v0.2.0...v0.3.0