Make base PriceList class abstract

src/PriceListTools/AbstractPriceList.cs

@@ -2,7 +2,7 @@
 
 namespace RehauSku.PriceListTools
 {
-    internal class PriceList
+    internal abstract class AbstractPriceList
     {
         protected const string amountHeader = "Кол-во";
         protected const string skuHeader = "Актуальный материал";

src/PriceListTools/Source.cs

@@ -7,7 +7,7 @@ using RehauSku.Interface;
 
 namespace RehauSku.PriceListTools
 {
-    internal class Source : PriceList
+    internal class Source : AbstractPriceList
     {
         public Dictionary<Position, double> PositionAmount { get; private set; }
 

src/PriceListTools/Target.cs

@@ -4,7 +4,7 @@ using System.Linq;
 
 namespace RehauSku.PriceListTools
 {
-    internal class Target : PriceList
+    internal class Target : AbstractPriceList
     {
         private const string oldSkuHeader = "Прежний материал";
         public Range oldSkuCell { get; private set; }

src/RehauSku.Assist.csproj

@@ -127,7 +127,7 @@
     <Compile Include="PriceListTools\Position.cs" />
     <Compile Include="PriceListTools\AbstractTool.cs" />
     <Compile Include="PriceListTools\MergeTool.cs" />
-    <Compile Include="PriceListTools\PriceList.cs" />
+    <Compile Include="PriceListTools\AbstractPriceList.cs" />
     <Compile Include="PriceListTools\Source.cs" />
     <Compile Include="PriceListTools\Target.cs" />
     <Compile Include="Interface\RibbonController.cs" />