Implement PDF rendering of cards and respective UI views

aleksis/apps/kort/admin.py

aleksis/apps/kort/migrations/0005_card_pdf_file.py

aleksis/apps/kort/models.py

aleksis/apps/kort/settings.py

aleksis/apps/kort/tables.py

aleksis/apps/kort/tasks.py

aleksis/apps/kort/templates/kort/card/actions.html

aleksis/apps/kort/templates/kort/card/detail.html

aleksis/apps/kort/templates/kort/card/detail_content.html

aleksis/apps/kort/templates/kort/card/list.html

aleksis/apps/kort/templates/kort/card/status.html

aleksis/apps/kort/templates/kort/pdf.html

aleksis/apps/kort/urls.py

aleksis/apps/kort/views.py