Cleanup and overhaul (#21)

* Syntax cleanup

* More minor cleanup, use Linq

* Fix broken features by using correct values

* Feature flags the same

* Features are modular

* No AlphaFS, more .NET versions

* Fix appveyor

* Put back identifiers, for some reason

* String interpolation, modernization

* Better use of GetField

* XmlTextWriter to remove possible issues

* Fix header for OpenMSX

SabreTools.Library/DatItems/BiosSet.cs

@@ -28,7 +28,7 @@ namespace SabreTools.Library.DatItems
         /// </summary>
         public BiosSet()
         {
-            this.Name = "";
+            this.Name = string.Empty;
             this.ItemType = ItemType.BiosSet;
         }
 
@@ -86,12 +86,10 @@ namespace SabreTools.Library.DatItems
         {
             // If we don't have a biosset, return false
             if (this.ItemType != other.ItemType)
-            {
                 return false;
-            }
 
             // Otherwise, treat it as a biosset
-            BiosSet newOther = (BiosSet)other;
+            BiosSet newOther = other as BiosSet;
 
             // If the archive information matches
             return (this.Name == newOther.Name && this.Description == newOther.Description && this.Default == newOther.Default);