Add email to the CoC

[FredrikAugust]

https://github.com/open-source-ideas/open-source-ideas/blob/master/CODE_OF_CONDUCT.md

As of now it says "INSERT EMAIL" which is not an email format I know, so perhaps consider changing it. If wanted mine can be used, but I think a shared one for @open-source-ideas/osii-maintainers would be best.

[mikaelbr]

Oh. Good catch. I've added my personal for now, but will create team email as soon as I can.