Do not limit MIME types during cronjob runs

Fix undefined constant if not on profile page

Fix too rigid capability check for avatar upload in admin UI

Take ALOT of arguments into account

Fix wrong argument for get_avatar()

Fix ID vs Email for get_avatar() and set a default

Enables setting a minimum image size

Fixes avatar upload not being generated

Limits BB/US placeholder to user profile screen

Fixes wrong filter name for avatar arguments