[Records] Custom discharge types

[mous13]

What problem would you like to solve?
Right now, we supply a limited list of discharge types, while there are a ton in the real military, which differs per country. The goal is to allow admins to configure what discharge types they'd like to utilise.

Lazy way to achieve this is using a text field that lets you define discharge types, separated by a ','. Which is then saved into a forumify setting entry as a json.

Preferable way to achieve this is utilising a collectionType to dynamically add and remove discharge types in a settings form, which is then saved into forumify's settings entity and can be called in the discharge form.