ファイル存在確認
//Documentsフォルダ内を確認
-(BOOL)isExistFile:(NSString*)fileName{
    NSString* path=[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];
    path=[path stringByAppendingPathComponent:fileName];
    return [[NSFileManager defaultManager] fileExistsAtPath:path];
}
//fullパスで確認
-(BOOL)isExistFileByFullPath:(NSString*)path{
    return [[NSFileManager defaultManager] fileExistsAtPath:path];
}