Update to Propel2 ORM

[juergmessmer]

Version 1.7 is completely outdated and always requires fixes.

Is future of Propel an issue: Propel2 or 3, or what. https://stackoverflow.com/questions/65676131/support-for-php-7-4-in-propel-1-7-x

[sabberworm]

IMHO Propel 2 is dead and Propel 3 is a complete re-write. If we’re willing to rewrite our code for that, we might as well switch to doctrine.

[sabberworm]

There is also a Propel 1 fork that may be more up-to-date: https://github.com/propeller-orm/propeller-orm

[juergmessmer]

There is also a Propel 1 fork that may be more up-to-date: https://github.com/propeller-orm/propeller-orm

For practical and stress reasons I can see this solution, or Propel2, since according to Thomas it is still maintained. But whatever. I see myself rather as tester and implementer, and would be happy if you guys would decide...