Add nullable context to SabreTools.DatItems

This change also starts migrating the internals of the DatItem formats to the new internal models. Right now, it's basically just acting like a wrapper around those models.

SabreTools.Core/Enums.cs

@@ -452,6 +452,12 @@ namespace SabreTools.Core
         [Mapping("configuration")]
         Configuration,
 
+        [Mapping("conflocation")]
+        ConfLocation,
+
+        [Mapping("confsetting")]
+        ConfSetting,
+
         [Mapping("control")]
         Control,
 
@@ -464,9 +470,15 @@ namespace SabreTools.Core
         [Mapping("device_ref", "deviceref")]
         DeviceReference,
 
+        [Mapping("diplocation")]
+        DipLocation,
+
         [Mapping("dipswitch")]
         DipSwitch,
 
+        [Mapping("dipvalue")]
+        DipValue,
+
         [Mapping("diskarea")]
         DiskArea,
 
@@ -491,9 +503,6 @@ namespace SabreTools.Core
         [Mapping("instance")]
         Instance,
 
-        [Mapping("location")]
-        Location,
-
         [Mapping("original")]
         Original,
 
@@ -521,9 +530,6 @@ namespace SabreTools.Core
         [Mapping("serials")]
         Serials,
 
-        [Mapping("setting")]
-        Setting,
-
         [Mapping("sharedfeat", "shared_feat", "sharedfeature", "shared_feature")]
         SharedFeature,