PAC can never fail silently

[buep]

It should always give an interpreted error message to the user, and in relevant occasion some stack trace information as well to supply the interpreted well explained error message.

This issues is created based on #89 where an issue apparently lead to PAC failing silently.

Goals:

• go through all exception and error handling in PAC ensuring it never fails silently.

[lakruzz]

@buep why is this sized as a briefing, is anything preventing this from being a real workable issue?

[lakruzz]

@buep
This issue is not assigned to any milestone - it therefore attracts attention, like an unread mail in your mailbox.

Where should it go?

[buep]

to a milestone when I read my incoming mail in the project... as I do now.