Add parameters to configure log rotation

[abitmore]

Currently log rotation of witness_node is hard-coded as

• one log file per hour and
• keep only log files created within one day.

It's better to change them to configurable for easier data analysis and trouble shooting. I personally want to keep the log files for at least one week.

Related code is here.

            // construct a default file appender config here
            // filename will be taken from ini file, everything else hard-coded here
            fc::file_appender::config file_appender_config;
            file_appender_config.filename = file_name;
            file_appender_config.flush = true;
            file_appender_config.rotate = true;
            file_appender_config.rotation_interval = fc::hours(1);
            file_appender_config.rotation_limit = fc::days(1);

[windycrypto]

Pls check this pr?
#840

[abitmore]

Merged #840. Closing.