reintroduce the variable name slot
ordering of variables
implement addition for multivariate polynomials
multiplication of multivariate polynomials
some generic math operations for rational functions (in fact for fractions in general)
fix small issue with variable tracking
add some special behaviour at the units of + * - /
avoid unnecessary calls to simplify, for the price of checking with simplified-p
optimise call structure for CLOS method resoution
make the multivariate poly and fractions code run
provide specialised zero-p and one-p methods for polynomials
Merge branch 'master' into multivariate-polynomials
explicitly pass the variable of polynomials around
make derivative respect variables
add a simple ggt implementation for polynomials
move fractions code into separate file
rename numer to numerator and denom to denominator
square roots and soaking up of rationals for fractions
check whether a polynomial is a square
always use 0 and 1 as answer to ZERO and ONE