Fix exclusive maximum validation error message

Author: zgyorffi

core/src/main/java/org/everit/json/schema/NumberSchemaValidatingVisitor.java

@@ -81,7 +81,7 @@ class NumberSchemaValidatingVisitor extends Visitor {
     @Override void visitExclusiveMaximumLimit(Number exclusiveMaximumLimit) {
         if (exclusiveMaximumLimit != null) {
             if (numberSubject >= exclusiveMaximumLimit.doubleValue()) {
-                owner.failure(format("is not less than " + exclusiveMaximumLimit), "exclusiveMaximum");
+                owner.failure(subject + " is not less than " + exclusiveMaximumLimit, "exclusiveMaximum");
             }
         }
     }

core/src/test/java/org/everit/json/schema/NumberSchemaTest.java

@@ -77,7 +77,7 @@ public void minimumFailure() {
     public void exclusiveMinimumLimit() {
         TestSupport.failureOf(NumberSchema.builder().exclusiveMinimum(10))
                 .expectedKeyword("exclusiveMinimum")
-                .expectedMessageFragment("is not greater than 10")
+                .expectedMessageFragment("10 is not greater than 10")
                 .input(10)
                 .expect();
     }
@@ -86,7 +86,7 @@ public void exclusiveMinimumLimit() {
     public void exclusiveMaximumLimit() {
         TestSupport.failureOf(NumberSchema.builder().exclusiveMaximum(10))
                 .expectedKeyword("exclusiveMaximum")
-                .expectedMessageFragment("is not less than 10")
+                .expectedMessageFragment("10 is not less than 10")
                 .input(10)
                 .expect();
     }