update developer commentary

for weapon traits, crates and palettes
clarify that you don't need to update the wiki page manually

OpenRA.Mods.RA/PaletteFromFile.cs

@@ -16,9 +16,13 @@ namespace OpenRA.Mods.RA
 {
 	class PaletteFromFileInfo : ITraitInfo
 	{
+		[Desc("internal palette name")]
 		public readonly string Name = null;
+		[Desc("If defined, load the palette only for this tileset.")]
 		public readonly string Tileset = null;
+		[Desc("filename to load")]
 		public readonly string Filename = null;
+		[Desc("Map listed indices to shadow. Ignores previous color.")]
 		public readonly int[] ShadowIndex = { };
 		public readonly bool AllowModifiers = true;