* lessEqOp -> lessEqualOp
* greaterEqOp -> greaterEqualOp
to avoid ambiguitity with other forms such as 'plusEqOp' where the
'Eq' implies an assigment. The name change also aligns better with
C++ <functional> names such as std::less_equal, std::greater_equal
ENH: simple labelRange predicates gt0/ge0/lt0/le0
- mirrors scalarRange tests.
Lower overhead than using labelMinMax::ge(0) etc since it does not
create an intermediate (is stateless) and can be used as a constexpr