Add support for multiple NavGraphs, make menu not block ui

[dbierek]

Enhancements:

• Adds support for multiple NavGraphs by updating NavWeakness to 2.0 (Thanks to @AnthonyFuller)

Fixes:

• Makes the menu not block the UI
• Updates the log for failure to load Obj to be more accurate
• Enable depth sort for PF Seed Point Box rendering
• Make NAVP and AIRG indices text render properly
• Fix hit test for Navp Areas and AIRG waypoints with indices >= 255
• Offset hit tests by 20 pixels vertically to account for the menu bar