* Add ability for a Lua sexp parameter to require a 'parent' parameter
* Add dockpoint as a return type
* variable conflicts
* var name
* qtfred
* address feedback
Several items here:
1. Patches several category and subcategory validation checks (comparisons to -1 rather than _NONE) that were missed in #4965.
2. Adds sanity checks to both built-in operators and scripted sexps to ensure categories and subcategories are consistent.
3. Deconflicts several built-in sexps that had inconsistent categories.
The inconsistent operators were:
* script-eval-string
* set-wing-formation
* get-ets-value
* turret-get-primary-ammo
* turret-get-secondary-ammo
* get-fov
Follow-up to #4965 and #4995.
* Add callback for user specified availability status
* Add target restrict hook
* Fix Restrict hook and add not self restrict type
* Fix documentation
* Fix typo
* scope the ai achievability enum
* fix scoped achievabiliy
Mike Nelson