Lots of monster stuff, particularly documenting monster abilities

- Monster radiate abilities can now specify a spell pattern to use
- Fix some abilities being incorrectly shown in the editor's ability details dialog (for example, radiate abilities were shown as "Summon aid")
- Add the recently-added monster missile types to the options offered in the editor
- Fix chance of activating not being editable for the martyr's shield ability
- Show the monster summoned for summoning abilities (finally!)
- Show the subcategory for unusual abilities (one of active, passive death)
- Fix the displayed percentage chance for summon abilities (the permille was shown instead)
- Fix incorrect action point display in the editor for the two recently-added monster missiles
- Fix crash when editing a missile ability
- Fix abilities page not showing the newly-added or recently-edited ability after exiting the detail/option dialog
- Fix pick monster button for summoning abilities being off by one

doc/editor/Monsters.html

@@ -141,6 +141,8 @@ aren't immune to fire.</li>
 node as its action, which can do anything a special node can do. This can be used to
 create special abilities that are otherwise not supported - for example, you could use
 this to make a monster that can teleport.</li>
+<li><b>Special when hit (Advanced) -</b> When you hit the monster with a weapon, a special
+node is called.</li>
 <li><b>Death Triggers Scenario Special (Advanced) -</b> The extra value is the number of a
 scenario special node, which is called when a creature of this type is killed.</li>
 <li><b>Custom Ability (Advanced) -</b> Most of the abilities listed above are pre-made