new actor/new action: auto-populate current user when creating interaction and/or contact

[tmfrnz]

allow to "opt out"

• [x] on new entity modal: checkbox option >> moved to #99
• [x] on regular new entity view: populate assigned user list with current user

[tmfrnz]

• [x] move to top
• [x] drop "Your changes" in multiselect dropdowns

[tmfrnz]

notes:

• auto-populating new entity form with "current user" for all action and actor types unless in modal (see #99 for exceptions)