Some cleanup using ReSharper (mostly removing redundancies)

Subsurface/Source/Characters/Jobs/Job.cs

@@ -1,8 +1,5 @@
-using Microsoft.Xna.Framework;
-using System;
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.Linq;
-using System.Text;
 using System.Xml.Linq;
 
 namespace Barotrauma
@@ -10,7 +7,7 @@ namespace Barotrauma
     class Job
     {
 
-        private JobPrefab prefab;
+        private readonly JobPrefab prefab;
 
         private Dictionary<string, Skill> skills;
 

Subsurface/Source/Characters/Jobs/JobPrefab.cs

@@ -160,7 +160,7 @@ namespace Barotrauma
             foreach (string filePath in filePaths)
             {
                 XDocument doc = ToolBox.TryLoadXml(filePath);
-                if (doc == null) return;
+                if (doc == null || doc.Root == null) return;
 
                 foreach (XElement element in doc.Root.Elements())
                 {

Subsurface/Source/Characters/Jobs/SkillPrefab.cs

@@ -1,17 +1,13 @@
 using Microsoft.Xna.Framework;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
 using System.Xml.Linq;
 
 namespace Barotrauma
 {
     class SkillPrefab
     {
-        string name;
+        private string name;
 
-        string description;
+        private string description;
 
         private Vector2 levelRange;