Update PdfDocument.java

set `_inflateOnMainThread=true` by default

Author: HendrixString

lib/src/main/java/com/hendrix/pdfmyxml/PdfDocument.java

@@ -48,7 +48,7 @@ public class PdfDocument implements IDisposable{
     // state of the rendering
     private boolean                             _isWorking              = false;
     // inflate on main thread
-    private boolean                             _inflateOnMainThread    = false;
+    private boolean                             _inflateOnMainThread    = true;
     // progress dialog
     private ProgressDialog                      _ringProgressDialog;
     // progress dialog message