Zune control of position and size of requester in Popasl class

[deadwood2]

Zune provides initial position and size to requesters it opens via Popasl class, however logic used to calculate these objects is somewhat questionable and results in each instance having different size and position. Review this approach and possibly allow to configure same as Prefs/Asl

https://ae.amigalife.org/index.php?topic=922.240.msg11656#msg11656