Arkworks serialization wrapped in Parity SCALE codec

ArkScale(T) can be serialized or deserialized using parity-scale-codec, provided T can be serialized or deserialized using ark-serialize.

Arkworks serializes via the std::io::{Read,Write} traits, or its no_std fork of those traits, as do other zcash sapling derivatives. At its core, Parity SCALE codec also consists of traits {Input,Output} analogous to std::io::{Read,Write} respectively, as well as traits {Decode,Encode} also quite similar to ark-serialize::{CanonicalDeserialize,CanonicalSerialize}. We simply translate between these extremely similar traits, including wrapping and unwrapping errors appropriately.