add -e/--export option to ferium list to print ids without formatting

[tippfehlr]

This is useful to quickly send a set of mods to someone who can just install them easily.

[theRookieCoder]

My biggest concern with this is the poor experience of having to manually add every single mod when 'importing' these IDs, which should be fixed by #175.
There is also a more in-depth export/import feature planned (#366), which I would prefer to an implementation like this.