Add workaround for Guidebook bug when importing with duplicates
Add workaround for Guidebook bug when importing with duplicates

GB seems to require unique session titles to allow using the
feature to replace duplicates during import, e.g. to update
existing schedules. We simply add the PK ID to each session
to make them unique.

Remove HTML tags from titles.

Reenable detecting poster sessions.

artcz/epcon,PythonSanSebastian/epcon,artcz/epcon,EuroPython/epcon,PythonSanSebastian/epcon,matrixise/epcon,artcz/epcon,matrixise/epcon,artcz/epcon,barrachri/epcon,PythonSanSebastian/epcon,malemburg/epcon,matrixise/epcon,PythonSanSebastian/epcon,malemburg/epcon,EuroPython/epcon,PythonSanSebastian/epcon,artcz/epcon,malemburg/epcon,barrachri/epcon,barrachri/epcon,artcz/epcon,PythonSanSebastian/epcon,malemburg/epcon,malemburg/epcon,barrachri/epcon,matrixise/epcon,malemburg/epcon,matrixise/epcon,matrixise/epcon,EuroPython/epcon,EuroPython/epcon,barrachri/epcon,barrachri/epcon