Blank 'Enemy Movement' subtab

Steps to recreate:

1. File->New
2. Quest->Enemies
3. Select any named enemy
4. Click 'Edit' button
5. Click 'Movement' tab
6. Click 'Enemy Movement' subtab
7. Observe nothing is on the subtab

I think there should at least be some help text on this subtab.

The "Enemy Movement" string comes from the enemy_movement_tabs array in zq_custom.cpp