www/piwigo: Update from 2.8.6 to 2.9.0

[joneum]

Summary

• www/piwigo: Update from 2.8.6 to 2.9.0
• Changelog: http://piwigo.org/releases/2.9.0

PR: 219985
Submitted by: Ralf van der Enden (maintainer)
Approved by: xxx (mentor)
#Differential Revision: https://reviews.freebsd.org/Dxxxxx

Test Plan

~/dev/ports/www/piwigo % portlint -AC
WARN: Makefile: for new port, make $FreeBSD$ tag in comment section empty, to make SVN happy.
WARN: /usr/home/joneum/dev/ports/www/piwigo/distinfo: [1]: TIMESTAMP is over 30 days old
0 fatal errors and 2 warnings found.

poudriere testport:

10amd64
10i386
11amd64
11i386
12.0-CURRENT r318899 amd64
12.0-CURRENT r318400 i386