Fixing crash occurring when creating a new bankroll

app/src/main/java/net/pokeranalytics/android/model/realm/Currency.kt

@@ -24,7 +24,9 @@ open class Currency : RealmObject() {
 
             val rate = value ?: 1.0
 
-            // could be async
+            // could be async?
+
+	        if (this.isManaged && this.realm != null) {
 
 		        val query = this.realm.where(ComputableResult::class.java)
 		        query.`in`("session.bankroll.currency.id", arrayOf(this.id))
@@ -43,3 +45,5 @@ open class Currency : RealmObject() {
 	        }
 
         }
+
+}