Fix null issues

Booru.Net.Tests/Program.cs

@@ -12,7 +12,7 @@ namespace Booru.Net.Tests
         {
             var BooruClient = new BooruClient();
 
-            var posts = await BooruClient.GetE621ImagesAsync("nintendo");
+            var posts = await BooruClient.GetRealBooruImagesAsync();
 
             Console.ReadLine();
         }

Booru.Net/Booru.Net.csproj

@@ -23,7 +23,7 @@ Yande.re</Description>
     <PackageTags>booru imageboard api wrapper</PackageTags>
     <PackageLicenseUrl>https://github.com/exsersewo/Booru.Net/blob/master/LICENSE</PackageLicenseUrl>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
-    <Version>1.0.0.2</Version>
+    <Version>1.0.0.3</Version>
   </PropertyGroup>
 
   <ItemGroup>

Booru.Net/Models/Boards/SafebooruImage.cs

@@ -27,7 +27,7 @@ namespace Booru.Net
 		public string Owner { get; set; }
 
 		[JsonProperty("parent_id")]
-		public int ParentID { get; set; }
+		public int? ParentID { get; set; }
 
 		[JsonProperty("rating")]
 		public Rating Rating { get; set; }
@@ -42,7 +42,7 @@ namespace Booru.Net
 		public int SampleWidth { get; set; }
 
 		[JsonProperty("score")]
-		public int Score { get; set; }
+		public int? Score { get; set; }
 
 		[JsonProperty("tags")]
 		private string Ptags { get; set; }