Add free noncommutative field
docfix: Thanks Riccardo Guida
docfixes
doc fix in List
Remove cycle related functions from Tree and BinaryTreeCategory
Optimize and add index range check for "index" in FiniteSetAggregate
add warning to "terms" function documentation
Generalize 'inverse' to DivisionRing
Cleanup duplicated and unused functions from Tree
Get inline optimization for some Integer functions