Added framework xml documentation for all "exploration" events.

ObservatoryFramework/Files/Journal/Exploration/BuyExplorationData.cs

@@ -1,8 +1,17 @@
 namespace Observatory.Framework.Files.Journal
 {
+    /// <summary>
+    /// Journal event generated when buying system data from the galaxy map while docked.
+    /// </summary>
     public class BuyExplorationData : JournalBase
     {
+        /// <summary>
+        /// Name of the system for which data was purchased.
+        /// </summary>
         public string System { get; init; }
+        /// <summary>
+        /// Amount paid for the data.
+        /// </summary>
         public int Cost { get; init; }
     }
 }