Release 0.1.0

[durban]

• [x] #57 Upgrade to FS2 0.10.0-M4
• [x] #59 Upgrade to Scala 2.12.3
• [x] double-check existing documentation
  • [x] tut
  • [x] README.md
  • [x] license + notice
• [x] add missing documentation
  • [x] add AUTHORS Certificate
  • [x] CONTRIBUTING.md
• [x] release
  • [x] update readme
  • [x] mention the fact, that artifacts are on maven central
  • [x] rephrase sentence about Typelevel Scala compatibility
  • [x] maven central / scaladex badge with latest version
  • [x] release artifacts
  • [x] GitHub release
  • [x] fix version reference in readme

[durban]

Done: https://github.com/durban/seals/releases/tag/v0.1.0.