LUA and trait documentation fixes

- Typo in documentation ("proximitry").
- Add spaces between sentences.
- Remove most occurrences of "  " (two spaces) unless clearly used as indendation
- Punctuation (although no fullstop after filenames like "notifications.yaml").

OpenRA.Mods.Common/Traits/Render/WithDecoration.cs

@@ -40,7 +40,7 @@ namespace OpenRA.Mods.Common.Traits
 		[Desc("Palette to render the sprite in. Reference the world actor's PaletteFrom* traits.")]
 		[PaletteReference] public readonly string Palette = "chrome";
 
-		[Desc("Point in the actor's bounding box used as reference for offsetting the decoration image." +
+		[Desc("Point in the actor's bounding box used as reference for offsetting the decoration image. " +
 			"Possible values are any combination of Top, VCenter, Bottom and Left, HCenter, Right separated by a comma.")]
 		public readonly ReferencePoints ReferencePoint = ReferencePoints.Top | ReferencePoints.Left;