Tool to make sure message tags are in sync

[mattias-p]

Messages are declared in multiple places. There's a profile file, a msgid table, a table of messages per test case, and an implementation of each test case. All these places must match up, and it's easy to forget updating one of them.

We should have a tool that checks all these places (preferably also cross referencing the specifications) and reports any discrepancies.

[matsduf]

I will update this issue and create an issue in zonemaster/zonemaster.