Email event translation not being validated before saving

We have various (around 130) emails (email events), that could be sent throughout the system, e.g. after user registration, order submit, etc.

When administrator, during email translation editing, accidentally damages one or more In-Portal tags in it, then such email won't be sent at all.

Even more, it will raise Fatal Error and PHP code after email sending won't be executed.

For example, when error is in ORDER.SUBMIT email event translation, then user's order stays in "Incomplete" status and won't move to "Pending" status, even, when it's payment was successful.

I propose we validate email event translation before allowing it to be saved back into database (by NParser::CompileRaw method). I don't think, that we should output fancy error messages, like NParser does. We could just show, that there are a "tag syntax error" in translation.