Docs: Add detail on customizing the forced groups

docs/options api.md

@@ -86,17 +86,29 @@ class ExampleWorld(World):
 ```
 
 ### Option Groups
-Options may be categorized into groups for display on the WebHost. Option groups are displayed alphabetically on the
-player-options and weighted-options pages. Options without a group name are categorized into a generic "Game Options"
-group.
+Options may be categorized into groups for display on the WebHost. Option groups are displayed in the order specified
+by your world on the player-options and weighted-options pages. In the generated template files, there will be a comment
+with the group name at the beginning of each group of options. The `start_collapsed` Boolean only affects how the groups
+appear on the WebHost, with the grouping being collapsed when this is `True`.
+
+Options without a group name are categorized into a generic "Game Options" group, which is always the first group. If
+every option for your world is in a group, this group will be removed. There is also an "Items & Location Options"
+group, which is automatically created using certain specified `item_and_loc_options`. These specified options cannot be
+removed from this group.
+
+Both the "Game Options" and "Item & Location Options" groups can be overridden by creating your own groups with
+those names, allowing specifying options to add to them, as well as change whether they start collapsed. The "Item &
+Location Options" group can also be moved to a different position in the group ordering, but "Game Options" will always
+be first, regardless of where it is in your list.
 
 ```python
 from worlds.AutoWorld import WebWorld
 from Options import OptionGroup
+from . import Options
 
 class MyWorldWeb(WebWorld):
     option_groups = [
-        OptionGroup('Color Options', [
+        OptionGroup("Color Options", [
             Options.ColorblindMode,
             Options.FlashReduction,
             Options.UIColors,