add ssl certificate fields for Monitor in default_config.xml

add ssl certificate generation for Monitor in plc.d/ssl

separate bootcd values from bootmanager configuration
build.sh now collects all the certificates that it needs to authenticate the
https sessions. As well, the BM configuration includes several new values that
control how and where it uploads logs.

BOOT_API_SERVER remains as the API server for all API calls
BOOT_SERVER is the host from which the bootstrapfs and other files are fetched.
MONITOR_SERVER is the host where logs are uploaded
UPLOAD_LOG_SCRIPT is the path to the upload script or entry point.

If the configuration value PLC_MONITOR_ENABLED=false, then MONITOR_SERVER=BOOT_SERVER
It is now much easier to extend BM in the future to upload additional files
such as for hardware information, SMART data, commands run by root users
during the session, etc.