OPDS Support (#526)

* Added some basic OPDS implementation

* Fixed an issue with feed href

* More changes

* Added library routes and moved user code to a method so we can hack in fixed code without authentication

* Images now load on the OPDS reusing our existing Image infrastructure.

* Added the ability to download and moved some download code to a dedicated service

* Download is working, pagination is implemented.

* Refactored libraries to use pagination

* Laid foundation for OpenSearch implementation

* Fixed up some serialization issues and some old code that wasn't referencing helper methods

* Ensure chapters are sorted when we send them over OPDS

* OpenSearch implemented

* Removed any support for OPDS-PS due to lack of apps supporting it.

* Don't distribute development.json nor stats directory on build.

* Implemented In Progress feed as well.

* Ability to enable OPDS for server. OPDS now accepts initial call as POST in case app uses username/password.

* UI now properly renders state for OPDS enablement. Added Collections routes.

* Fixed pagination startIndex on OPDS feeds when there is less than 1 page.

* Chunky Reader now works. It only accepts UTF-8 encodings

* More Chunky fixes

* More chunky changes, such a fussy client.

* Implemented the ability to have a custom api key assigned to a user and use that api key as your authentication token against OPDS routing.

* Implemented the ability to reset your API Key

* Fixed favicon not being sent back correctly

* Fixed an issue where images wouldn't send on OPDS feed.

* Implemented Page streaming and fixed a pagination bug

* Hooked in the ability to save progress in Kavita when Page Streaming

Kavita.Common/HashUtil.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Security.Cryptography;
 using System.Text;
 
 namespace Kavita.Common
@@ -37,5 +38,20 @@ namespace Kavita.Common
             var seed = $"{Environment.ProcessorCount}_{Environment.OSVersion.Platform}_{Configuration.JwtToken}_{Environment.UserName}";
             return CalculateCrc(seed);
         }
+
+        /// <summary>
+        /// Generates a unique API key to this server instance
+        /// </summary>
+        /// <returns></returns>
+        public static string ApiKey()
+        {
+            var id = Guid.NewGuid();
+            if (id.Equals(Guid.Empty))
+            {
+                id = Guid.NewGuid();
+            }
+
+            return id.ToString();
+        }
     }
 }