net-mgmt/librenms: Update to 1.35, many improvements

Improvements:

• All files should be owned root:wheel except logs and rrd which need to be writable by the app
• Add missing php posix extension
• Do not install config.php by default. This breaks the install process which won't run if this file exists
• Clean up automatic PLIST creation: don't install .orig or .bak files, don't add @dir as they aren't needed
• Patch LibreNMS to make /validate/ page not produce warnings about files not being writable (for git updates)
• Remove the Updates validation check altogether as we won't be using git to update
• Patch the User validation check to only check the logs and rrd dir and ensure the correct user owns them
• Change the default user in the generated config to "www"
• Patch the File Lock code to put the lock file in /tmp and not in the WWWDIR which should not be writable
• Update message in installer to use WWWDIR as suggested path for config.php
• Use shebangfix instead of patch where applicable
• Fix APACHEMOD port option and declaration of the USES=php

PR: 225161
MFH: 2018Q1
Differential Revision: https://reviews.freebsd.org/D13907