Removed validation for negative values in conditional formatting priority, as negative values should be allowed.

Author: JanKallman

src/EPPlus/ConditionalFormatting/ExcelConditionalFormattingColorScaleValue.cs

@@ -72,7 +72,6 @@ internal ExcelConditionalFormattingColorScaleValue(
                 namespaceManager,
                 itemElementNode)
         {
-            Require.Argument(priority).IsInRange(1, int.MaxValue, "priority");
             Require.Argument(address).IsNotNull("address");
             Require.Argument(worksheet).IsNotNull("worksheet");
 

src/EPPlus/ConditionalFormatting/ExcelConditionalFormattingIconDatabarValue.cs

@@ -70,8 +70,6 @@ internal ExcelConditionalFormattingIconDataBarValue(
             itemElementNode,
 			namespaceManager)
 		{
-			Require.Argument(priority).IsInRange(1, int.MaxValue, "priority");
-
             // Check if the parent does not exists
 			if (itemElementNode == null)
 			{

src/EPPlus/ConditionalFormatting/ExcelConditionalFormattingRuleFactory.cs

@@ -34,7 +34,6 @@ public static ExcelConditionalFormattingRule Create(
 		{
 			Require.Argument(type);
       Require.Argument(address).IsNotNull("address");
-      //Require.Argument(priority).IsInRange(0, int.MaxValue, "priority");  // Priority can be negative, so remove this check.
       Require.Argument(worksheet).IsNotNull("worksheet");
 
 			// According the conditional formatting rule type

src/EPPlus/ConditionalFormatting/Rules/ExcelConditionalFormattingRule.cs

@@ -67,7 +67,6 @@ internal ExcelConditionalFormattingRule(
         itemElementNode)
     {
       Require.Argument(address).IsNotNull("address");
-      Require.Argument(priority).IsInRange(0, int.MaxValue, "priority");
       Require.Argument(worksheet).IsNotNull("worksheet");
 
       _type = type;