Give more details for exception throw

app/src/main/java/net/pokeranalytics/android/model/utils/SessionSetManager.kt

@@ -23,8 +23,11 @@ class SessionSetManager {
 				throw IllegalStateException("realm should be in transaction at this point")
 			}
 
-			if (session.startDate == null || session.endDate == null) {
+			if (session.startDate == null) {
-				throw IllegalStateException("Start or end date should never be null here")
+				throw IllegalStateException("Start date should never be null here")
+			}
+			if (session.endDate == null) {
+				throw IllegalStateException("End date should never be null here")
 			}
 			val endDate = session.endDate!! // tested above
 			val startDate = session.startDate!!