Moved files and introduced IMarkdownToHtmlConverter to avoid packages to handle markdown in core

Signed-off-by: Bjarke Berg <mail@bergmania.dk>

src/Umbraco.Core/Configuration/Extensions/HealthCheckSettingsExtensions.cs

@@ -0,0 +1,27 @@
+using System;
+using Umbraco.Core.Configuration.Models;
+
+namespace Umbraco.Core.Configuration.Extensions
+{
+    public static class HealthCheckSettingsExtensions
+    {
+        public static TimeSpan GetNotificationDelay(this HealthChecksSettings settings, ICronTabParser cronTabParser, DateTime now, TimeSpan defaultDelay)
+        {
+            // If first run time not set, start with just small delay after application start.
+            var firstRunTime = settings.Notification.FirstRunTime;
+            if (string.IsNullOrEmpty(firstRunTime))
+            {
+                return defaultDelay;
+            }
+            else
+            {
+                // Otherwise start at scheduled time according to cron expression, unless within the default delay period.
+                var firstRunOccurance = cronTabParser.GetNextOccurrence(firstRunTime, now);
+                var delay = firstRunOccurance - now;
+                return delay < defaultDelay
+                    ? defaultDelay
+                    : delay;
+            }
+        }
+    }
+}