Small improvements strings documentation

* Use new 'Returns:' and 'Inputs:' keywords used by the website generator
* Make order item order resemble website, i.e. 'Returns:' comes before
  'Example:'
* Add a few missing input items
* Add a few missing return items

core/strings/ascii_set.odin

@@ -12,10 +12,10 @@ Ascii_Set :: distinct [8]u32
 /*
 Creates an Ascii_Set with unique characters from the input string.
 
-**Inputs**  
+Inputs:
 - chars: A string containing characters to include in the Ascii_Set.
 
-**Returns**  
+Returns:
 - as: An Ascii_Set with unique characters from the input string.
 - ok: false if any character in the input string is not a valid ASCII character.
 */
@@ -33,11 +33,11 @@ ascii_set_make :: proc(chars: string) -> (as: Ascii_Set, ok: bool) #no_bounds_ch
 /*
 Determines if a given char is contained within an Ascii_Set.
 
-**Inputs**  
+Inputs:
 - as: The Ascii_Set to search.
 - c: The char to check for in the Ascii_Set.
 
-**Returns**  
+Returns:
 A boolean indicating if the byte is contained in the Ascii_Set (true) or not (false).
 */
 ascii_set_contains :: proc(as: Ascii_Set, c: byte) -> bool #no_bounds_check {