have the translations remain if the plugin is disabled

Comes from https://answers.atlassian.com/questions/44201/how-can-you-change-the-translations-in-your-own-jira-instance/82098

We could add setting to disable 'start translation' option so there is no possibility to translate but all existing translations are correctly displayed.
I'm not sure if that makes sense or maybe it is redundant if we want to add 'export language pack' and 'tac integration' features.
It can make sense for some private translations (so tac integration is not an option).
It could be also simpler to change one switch in the plugin than exporting and installing language pack.