Add haskell-tagged-transformer 0.7.1
Merge pull request #3883 from dmalikov/haskell-tagged-transformer

Add haskell-tagged-transformer 0.7.1
mcabber: fix mispelled stdenv
lirc: add missing semicolon
qemu: 2.0.0 -> 2.1.0

Additionally, add support for more external features as well as more
sound system types.