fixed text rasterization problem for some pdf's, it seems that the 'pdfopen begin' did not initialize everything required to render pdf properly so we replaced it with the 'runpdfopen' method which corrects everything (problem reported by "xatabhk")

Author: jhabjan

Ghostscript.NET/Viewer/FormatHandlers/GhostscriptViewerPdfFormatHandler.cs

@@ -94,8 +94,8 @@ GS_PDF_ProcSet begin
         public override void Open(string filePath)
         {           
             // open PDF file
-            this.Execute(string.Format("({0}) (r) file pdfopen begin", filePath.Replace("\\", "/")));
-
+            this.Execute(string.Format("({0}) (r) file runpdfbegin", filePath.Replace("\\", "/")));
+            
             this.Execute("/FirstPage where { pop FirstPage } { 1 } ifelse");
             this.Execute("/LastPage where { pop LastPage } { pdfpagecount } ifelse");