Printing in WPF port for .NET (#1156)

* Initial files

* update toc

* Content update - print-xps-files (user story 1861941) (#1151)

* Add C# and VB sample code projects

* Fix comments

* Update C# and VB code

* Add article

* Further edits

* Reviewer requested edits

* Further edits

* Use xref to link to API

* Minor edits

* Content update - invoke-print-dialog (user story 1861941) (#1141)

* Content update including C# WPF project

* Fix link

* Remove test code

* Further doc and C# sample edits

* Add feature: printing with no print dialog

* Separate out specific page range print functionality

* Cleanup comments

* UI tweaks

* Add VB sample code project

* Code file formatting

* Update dotnet-desktop-guide/net/wpf/documents/how-to-display-print-dialog.md

Co-authored-by: Andy (Steve) De George <[email protected]>

* Add page range printing

* Minor edits

* Update dotnet-desktop-guide/net/wpf/documents/snippets/how-to-display-print-dialog/csharp/MainWindow.xaml.cs

Co-authored-by: Andy (Steve) De George <[email protected]>

* Update dotnet-desktop-guide/net/wpf/documents/how-to-display-print-dialog.md

Co-authored-by: Andy (Steve) De George <[email protected]>

* Promote example headings

* Reorganize and add detail

* Minor edits

* Add detail

* Further edits

* Further edits

* Add resource links

* Add alternative API suggestions to a tip

* Minor edit

Co-authored-by: Andy (Steve) De George <[email protected]>

* Content update - print-overview (user story 1861941) (#1153)

* Add C# and VB sample code projects

* Add article

* Add redirects

Co-authored-by: Tris Shores <[email protected]>

dotnet-desktop-guide/net/wpf/toc.yml

@@ -47,6 +47,20 @@ items:
           href: controls/how-to-create-apply-style.md
         - name: Create and apply a template
           href: controls/how-to-create-apply-template.md
+  - name: Documents & Printing
+    items:
+    - name: Printing
+      expanded: true
+      items:
+      - name: Overview
+        href: documents/printing-overview.md
+      - name: Common tasks
+        items:
+        - name: Display the print dialog
+          href: documents/how-to-display-print-dialog.md
+        - name: Programmatically print XPS files
+          href: documents/how-to-print-xps-files.md
+    
   - name: Data binding
     items:
     - name: Overview