- More code cleanup and codestyle updates

- Fixed some possible nullref exceptions
- Methods signatures now have up to 3 parameters before breakaing down each parameter in a separate line
- Method invocations have the same rule, except the first parameter will be in the same line as the invocation to prevent some ugliness when passing lambas as arguments
- Applied many more codestyles
- Extensions folder fully reformatted

src/NadekoBot/Db/Models/ClubInfo.cs

@@ -23,9 +23,7 @@ public class ClubInfo : DbEntity
     public string Description { get; set; }
 
     public override string ToString()
-    {
-        return Name + "#" + Discrim;
-    }
+        => Name + "#" + Discrim;
 }
 
 public class ClubApplicants