Simplify return statements.

Remove redundant ‘this’.
Remove unused using directives.
Simplify LINQ chains.
Add some trait property descriptions.
Add readonly where viable.
Add fullstops to some yaml descriptions.

OpenRA.Game/Group.cs

@@ -15,8 +15,8 @@ namespace OpenRA
 {
 	public class Group
 	{
-		Actor[] actors;
-		int id;
+		readonly Actor[] actors;
+		readonly int id;
 
 		static int nextGroup;
 

OpenRA.Game/Traits/CreatesShroud.cs

@@ -20,7 +20,7 @@ namespace OpenRA.Traits
 
 	public class CreatesShroud : ITick, ISync
 	{
-		CreatesShroudInfo info;
+		readonly CreatesShroudInfo info;
 		[Sync] CPos cachedLocation;
 		[Sync] bool cachedDisabled;
 

OpenRA.Game/Traits/DebugPauseState.cs

@@ -18,7 +18,7 @@ namespace OpenRA.Traits
 
 	public class DebugPauseState : ISync
 	{
-		World world;
+		readonly World world;
 		[Sync] public bool Paused { get { return world.Paused; } }
 		public DebugPauseState(World world) { this.world = world; }
 	}

OpenRA.Game/Traits/DrawLineToTarget.cs

@@ -33,7 +33,7 @@ namespace OpenRA.Traits
 
 		public void SetTarget(Actor self, Target target, Color c, bool display)
 		{
-			this.targets = new List<Target> { target };
+			targets = new List<Target> { target };
 			this.c = c;
 
 			if (display)

OpenRA.Game/Traits/Health.cs

@@ -110,7 +110,7 @@ namespace OpenRA.Traits
 			if (IsDead)
 				return;
 
-			var oldState = this.DamageState;
+			var oldState = DamageState;
 
 			// Apply any damage modifiers
 			if (!ignoreModifiers && damage > 0)
@@ -128,7 +128,7 @@ namespace OpenRA.Traits
 			{
 				Attacker = attacker,
 				Damage = damage,
-				DamageState = this.DamageState,
+				DamageState = DamageState,
 				PreviousDamageState = oldState,
 				Warhead = warhead,
 			};

OpenRA.Game/Traits/LintAttributes.cs

@@ -12,7 +12,7 @@ using System;
 
 namespace OpenRA.Traits
 {
-	/* attributes used by RALint to understand the rules */
+	/* attributes used by OpenRA.Lint to understand the rules */
 
 	[AttributeUsage(AttributeTargets.Field)]
 	public sealed class ActorReferenceAttribute : Attribute { }

OpenRA.Game/Traits/RevealsShroud.cs

@@ -20,7 +20,7 @@ namespace OpenRA.Traits
 
 	public class RevealsShroud : ITick, ISync
 	{
-		RevealsShroudInfo info;
+		readonly RevealsShroudInfo info;
 		[Sync] CPos cachedLocation;
 
 		public RevealsShroud(RevealsShroudInfo info)

OpenRA.Game/Traits/Selectable.cs

@@ -28,7 +28,7 @@ namespace OpenRA.Traits
 	public class Selectable : IPostRenderSelection
 	{
 		public SelectableInfo Info;
-		Actor self;
+		readonly Actor self;
 
 		public Selectable(Actor self, SelectableInfo info)
 		{

OpenRA.Game/Traits/SelectionDecorations.cs

@@ -28,7 +28,7 @@ namespace OpenRA.Traits
 		static readonly string[] TagStrings = { "", "tag-fake", "tag-primary" };
 
 		public SelectionDecorationsInfo Info;
-		Actor self;
+		readonly Actor self;
 
 		public SelectionDecorations(Actor self, SelectionDecorationsInfo info)
 		{