=== Incomplete awlsim TODO list ===

S7 compatibility:
- Implement parsing of attributes

core:
- Blocks that are no longer linked to (created by) sources should be removed.
- Single download of symtab causes a redefinition error.

GUI:
- Save window status (open MDI windows, positions, etc)
- Qt5: Title bar buttons in MDI windows do not work
- Show UDTs in block tree
