Remove trailing ; at metadata

[koppor]

While reading test cases of the metadata serialization, I saw that the final ; seems to be mandatory (e.g., tobiasdiez@174b49b).

Is that true? Can we get rid of that? This feels so 90ies ;).

[simonharrer]

No objections, but we still need to be able to parse the old format. But we can write the new one.

[stefan-kolb]

Also see #1331 Maybe this even is an issue?

[tobiasdiez]

I think this the trailing ; is not a big deal and we should focus on JabRef#232 if we really want to improve our metadata serialization -> closed (if you really want this, reopen or better implement it directly)