v0.40.6

AbstractAlgebra v0.40.6

Diff since v0.40.5

Merged pull requests:

• Centralize import/export statements and clean up main file (#1537) (@lgoettgens)
• Move FracField methods for concrete type to right place (#1650) (@fingolfin)
• Address some flaws with stale imports (#1652) (@lgoettgens)
• Sort out some generic/concrete poly code (#1655) (@lgoettgens)
• Add include_deprecated_bindings (#1656) (@lgoettgens)
• chore: bump to 0.40.6 (#1657) (@lgoettgens)

Closed issues:

• Methods for finding factors and roots of a polynomial in AbstractAlgebra.jl (#1644)