Fixed warnings in gap.plot() when there were 2 gaps.

Fixed pie3D() which skipped very small slices (issue #9).

Fixed polar.plot() which put labels in the wrong place (PR #8).

Fixed plotCI() to allow pch to be a vector (PR #11).

Added arguments to gap.plot() to support non-standard
box types (PR #17).

Added pkgdown site at https://plotrix.github.io/plotrix/

Changed Authors to more descriptive Authors@R.

Duncan Murdoch has taken over as maintainer.

Source has been moved to Github.

A bug in the labels in pyramid.plot() reported by biohisham
has been fixed.