Remove planned deprecated '--sourceaddr' option

[tgreenx]

Purpose

This PR removes planned deprecated --sourceaddr option.

Context

Relates to zonemaster/zonemaster-engine#1343

How to test this PR

There should be no trace in the code, or documentation of the --sourceaddr option.

Also:

$ zonemaster-cli zonemaster.net --sourceaddr 1.2.3.4
Unknown option: --sourceaddr
Run "zonemaster-cli -h" to get the valid options

[marc-vanderwal]

Successfully tested without issues.

The command-line option --sourceaddr is no longer recognized.

I couldn’t find any trace of --sourceaddr in the documentation of zonemaster-cli --help, nor in man zonemaster-cli.

The msgids in the .po files still mention --sourceaddr but I presume that these will be removed at the next translation update.