sorry for the omnibus

  * fixed off-by-one bug in multVM

  * fixed the problem with the Wikipedia code; it works now

  * improved debugging format in Haskell.Decode

  * new ECC type parameter for extra decoder outpu (eg number of iterations)

  * added the Noise module; basically copied from the hfec repo

  * the mutable array-based ECC handles some noise, but needs stronger testing