security/sshguard: Update to 2.1.0

Improve descriptions, pkg-message and update WWW.

Changes: https://sourceforge.net/p/sshguard/mailman/message/36109171/

PR: 224153
Submitted by: Kevin Zheng <kevinz5000@gmail.com>
Approved by: maintainer timeout (dan.mcgregor@usask.ca, > 2 weeks)