update git repo creation to handle collection papers

remove https from gitlab url

add python-gitlab package to requirements
add gitlab variables to settings
add advance repos django command

remove https from gitlab url

add python-gitlab package to requirements
add gitlab variables to settings
add advance repos django command

Authors will now be able to attach files to
their feedback form for the proofs sent by the production
team. The attachment is linked to the ProductionEvent that
is created with the feedback.