ports/189159: update for ports/sysutils/zfs-snapshot-clean

[Masato Minda]

>Number:         189159
>Category:       ports
>Synopsis:       update for ports/sysutils/zfs-snapshot-clean
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          update
>Submitter-Id:   current-users
>Arrival-Date:   Thu May 01 04:20:00 UTC 2014
>Closed-Date:
>Last-Modified:
>Originator:     Masato Minda
>Release:        10.0 RELEASE
>Organization:
WIDE Project.
>Environment:
FreeBSD brunehaut.minda.jp 10.0-RELEASE-p2 FreeBSD 10.0-RELEASE-p2 #0: Tue Apr 29 17:06:01 UTC 2014     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
zfs-snapshot-clean is nice. But I've fixed three issues and added some little enhancement.

1. There is no PATH setting.

2. This scripts supports only mounted ZFS. However I am using non-mounted ZFS.

3. On Solaris, This script does not work. Because /bin/sh on Solaris does not support "$(command)" syntax.

And... Solaris must need GNU date command :-(
>How-To-Repeat:

>Fix:
Here is patch for 0.1.3 

>Release-Note:
>Audit-Trail:
>Unformatted: