v0.7.0 - cats 2.x, cats-effect 2.x, http4s 0.21, new modules

Another "stable" (at least until another minor version bump) release of sup!

It took quite a long time (0.6.0 was released on August 15, 2019), but since all the dependencies were released as stable for 2.13 we're there.

Since 0.6.0, we got:

New features

• Scala 2.13 support
• akka-http server module (contributed by @DennisVDB, thanks a lot!)

Dependency updates

• Scala 2.12.8 -> 2.12.10
• cats-effect 1.4.0 -> 2.1.1
• cats-tagless 0.5 -> 0.11
• cats-par was dropped
• doobie 0.7.0 -> 0.8.8
• cats 1.6.1 -> 2.1.0
• simulacrum was removed
• refined was removed in favor of a FiniteDuration in the doobie module
• redis4cats 0.8.2 -> 0.9.3
• log4cats 0.3.0 -> 1.0.1
• http4s 0.20.10 -> 0.21.0
• circe 0.11.1 -> 0.13.0 (also, circe-generic was removed in favor of handwritten codecs, thanks to @xplosunn!)
• sttp 1.6.4 -> 1.7.2

Housekeeping

• Added scalafmt configuration
• Moved from tut to mdoc for the microsite
• Moved from custom tpolecat flags to sbt-tpolecat

Breaking changes

• Scala 2.11 support was dropped
• Some method signatures are binary incompatible, but they should be fine on source level.