propellor 5.3.6 released with these changes

  • Fix build with ghc 8.4, which broke due to the Semigroup Monoid change.
  • Dropped support for building propellor with ghc 7 (as in debian oldstable), to avoid needing to depend on the semigroups transitional package, but also because it's just too old to be worth supporting.
  • stack.yaml: Updated to lts-9.21.
  • Make Schroot.overlaysInTmpfs revertable Thanks, Sean Whitton
  • Update shim each time propellor is run in a container, to deal with library version changes.
  • Unbound: Added support for various DNS record types. Thanks, FĂ©lix Sipma.