More type class instances!

Some of the things in here:

Monoid[_ <: Seq[_]], Module[_ <: Seq[_]: Ring], VectorSpace[_ <: Seq[_]: Field], etc.
Lp NormedVectorSpaces for Seq-likes.
Eq[_ <: Seq[_]], Order[_ <: Seq[_]]
Monoid[Array[_]], Module[Array[_]: Ring], VectorSpace[Array[_]: Field], etc.
Eq[Array[_]], Order[Array[_]]
Monoid[Map[_, _]: Semigroup], Group[Map[_, _]: Group], Rng[Map[_, _]], etc.
Eq[Map[_, _]]
Monoid[Option[_]], Eq[Option[_]]

Tuple instances (as external product) for Semigroup, Monoid, Group, AbGroup, Semiring, Rig, Rng, Ring, EuclideanRing, Field, NRoot, Eq, Order.

Monoid[String], MetricSpace[String, Int] (Levenshtein distance).

There is probably some more too...