textproc/jshon: Update to 20170302.1

• Take over MAINTAINER'ship.
• Sort variables.
• Remove the COMMIT_HASH variable. Use only GH_TAGNAME instead.
• Add ZSH to OPTIONS_DEFAULT as suggested by the handbook.
• Do not strip in post-install since INSTALL_PROGRAM is already used in do-install.
• Improve pkg-descr.

Reviewed by: krion
Approved by: krion (mentor)
Differential Revision: https://reviews.freebsd.org/D18422