• make it build against system hiredis, instead of bundled one
• bump PORTREVISION because of dependency change

while here:

• trim Makefile header
• tab -> space change in pkg-descr:WWW

PR: 172090
Submitted by: Kubilay Kocak <koobs.freebsd at gmail dot com>
Approved by: Denis Generalov <gd at rambler-co dot ru> (maintainer)