add elixir-style tarr![A, B, C | Rest] (where Rest: TypeArray) capturing of the rest of the array

[kgullion]

Adds new patterns to the tarr! macro to support elixir-style matching

Handy for "recursively" iterating on a TypeArray.

eg

pub trait IndexOf<V> {
    type Idx: Unsigned;
    type Found: Bit;
}
impl<V> IndexOf<V> for tarr![] {
    type Idx = U0; // Always zero if not found
    type Found = B0;
}
impl<V, HD, TL: IndexOf<V>> IndexOf<V> for tarr![HD | TL]
where
    V: IsEqual<HD, Output: BitOr<TL::Found, Output: Bit>>,
    TL::Idx: Add<TL::Found, Output: Unsigned>,
{
    type Idx = Sum<TL::Idx, TL::Found>; // Add one if V in TL
    type Found = Or<Eq<V, HD>, TL::Found>;
}

btw, I've been using this lib (mostly TArr and Unsigned) pretty heavily. might put together a PR for some more of my utils in the future but link for the curious.