Holiday Bugfixes (#1762)

* Don't show "not much going on" when we are actively downloading

* Swipe to paginate is now behind a flag in the user preferences.

* Added a new server setting for host name, if the server sits behind a reverse proxy. If this is set, email link generation will use it and will not perform any checks on accessibility (thus email will always send)

* Refactored the code that checks if the server is accessible to check if host name is set, and thus return rue if so.

* Added back the system drawing library for markdown parsing.

* Fixed a validation error

* Fixed a bug where folder watching could get re-triggered when it was disabled at a server level.

* Made the manga reader loader absolute positioned for better visibility

* Indentation

API/DTOs/UserPreferencesDto.cs

@@ -46,6 +46,11 @@ public class UserPreferencesDto
     /// </summary>
     [Required]
     public string BackgroundColor { get; set; } = "#000000";
+    [Required]
+    /// <summary>
+    /// Manga Reader Option: Should swiping trigger pagination
+    /// </summary>
+    public bool SwipeToPaginate { get; set; }
     /// <summary>
     /// Manga Reader Option: Allow the menu to close after 6 seconds without interaction
     /// </summary>