modify properties file to yaml file.

[HessTina-YuI]

No description provided.

[Oseenix]

LGTM

[Oseenix]

1. for CONFIG_FILE has been changed to 'agent.yaml', maybe the parse method should not be the extractPropsMap which is used to parse property file.
2. the agent.yaml is not exist, could you help to generate it.

[akwei]

Better as follows:

if (file.getName().endsWith(".properties")) {
    ////
} else if (file.getName().endsWith(".yaml") || file.getName().endsWith(".yml")) {
    ///
} else {
    LOGGER.warn("can not load config file: {}", file.getAbsolutePath());
}

[Oseenix]

    private static boolean checkYaml(String filename) {
        return filename.endsWith(".yaml") || filename.endsWith(".yml");
    }

    private static GlobalConfigs loadFromClasspath(ClassLoader classLoader, String file) {
        try (InputStream in = classLoader.getResourceAsStream(file)) {
            if (in != null) {
                Map<String, String> map;
                if (checkYaml(file)) {
                    try {
                        map = new YamlReader().load(in).compress();
                    } catch (ParserException e) {
                        LOGGER.warn("Wrong Yaml format, load config file failure: {}", file);
                        map = Collections.emptyMap();
                    }
                } else {
                    map = extractPropsMap(in);
                }
                return new GlobalConfigs(map);
            }
        } catch (IOException e) {
            LOGGER.warn("Load config file:{} by classloader:{} failure: {}", file, classLoader.toString(), e);
        }

        return new GlobalConfigs(Collections.emptyMap());
    }