events: allow editing of all used values

Allow to change the date/time and
other relevant values of an event
on creation and after it was created.

app/src/main/java/it/danieleverducci/lunatracker/MainActivity.kt

@@ -593,7 +593,7 @@ class MainActivity : AppCompatActivity() {
         d.setView(dialogView)
 
         d.setNeutralButton(R.string.dialog_event_detail_delete_button) { dialogInterface, i ->
-            deleteEvent(event)
+            deleteEvent(originalEvent)
             dialogInterface.dismiss()
         }