We implement (multivariate) Taylor series.

Note that there is no easy well-defined notion of multivariate Laurent series, which is why we create a new class.

Depends on #32309
Depends on #34330

CC: @tscrim @tejasvicsr1 @slel

Component: combinatorics

Keywords: LazyPowerSeries, FormalSeries

Author: Martin Rubey

Branch/Commit: e780472

Reviewer: Travis Scrimshaw

Issue created by migration from https://trac.sagemath.org/ticket/32324