Sylvia/docs/sfd

@mhoeber @lamagnifica SFD_ORA.rst and SFD_mathformatting.rst are ready for a dev review when you guys have the time. (SFD_certificates is still in the writing phase, so ignore that one for now.) Thanks!
Good questions - ORA1 allowed computer code and video submissions, but ORA2 currently only allows text and text+image. I've updated the text at the beginning of the topic.