A benchmark for processing combinators
Add deepseq to build-depends for the benchmark
MPD.Handle (recv): wait for timeout at the beginning, not during

Wait before starting the loop.
If we time out, throw an exception, otherwise run the loop.
Assume that once we have begun receiving, we will get an
exception (EOF, ResourceVanished) if a problem occurs during
the operation.
MPD.Handle (recv): imperative style is more natural here
MPD.Handle (getResponse): update haddock to reflect change in recv
Merge branches 'missing-dep', 'processing-bench', 'recv-wait-first' and 'imperative-recv'