Various special node fixes/tweaks

- Fix secret passage nodes (CANT_ENTER with ex1a = 0, ex2a = 1) not working
- Set many flags now sets the entire row of 50 flags
- Division node now accepts either SDF to be null
- New mode for append item to buffer - adds the item's "interesting string" rather than its name
- Affect mage/priest spell inverted the meaning of ex1b relative to other affect nodes; this has been fixed
- Fix affect party status being confused about which fields mean what (the implementation had one idea, and the porting of old scenarios had a different idea, and the scenario editor had yet a different idea). In addition, it now allows removing the statuses.
- Fix some typos in special node information for the editor

rsrc/strings/specials-text-affect.txt

@@ -297,7 +297,7 @@ Unused
 Amount (0 .. 10)
 0 - increase, 1 - decrease
 Unused
-Statistic to adjust (0..21)
+Statistic to adjust (0..20)
 Unused
 Unused
 Special to Jump To
@@ -311,7 +311,7 @@ Unused
 Unused
 Unused
 Which Spell (0 .. 61)
-0 - remove, 1 - give
+1 - remove, 0 - give
 Unused
 Unused
 Unused
@@ -327,7 +327,7 @@ Unused
 Unused
 Unused
 Which Spell (0 .. 61)
-0 - remove, 1 - give
+1 - remove, 0 - give
 Unused
 Unused
 Unused
@@ -391,11 +391,11 @@ Unused
 Unused
 Unused
 Amount (0 .. 250)
+0 - increase, 1 - decrease
+Unused
 Which effect (0 .. 3)
 Unused
 Unused
-Unused
-Unused
 Special to Jump To
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