Merge pull request #43 from aliueKurone/for_pull_request

solved "An error occurred while saving." problem

Classes/FRAProject.m

@@ -591,7 +591,7 @@ - (void)cleanUpDocument:(id)document
 		[self setFirstDocument:nil];
 	}
 
-	[FRAManagedObjectContext deleteObject:document];
+    [documentsArrayController removeObject:document];
 	[[FRAApplicationDelegate sharedInstance] saveAction:nil]; // To remove it from memory
 	[[FRAManagedObjectContext undoManager] removeAllActions];
 }