sysutils/catfish: Update to 1.4.6

• Also update WWW now that catfish is part of the Xfce project
• Set maintainer to xfce@ now that catfish is part of the Xfce project

Changes this release:

https://mail.xfce.org/pipermail/xfce-announce/2018-July/000626.html

PR: 229850
Approved by: jpaetzel (maintainer)