CMe3100 Add-on license Modbus

By purchasing a feature license, new services can be enabled for CMe3100, for example Modbus, REST or JSON.

N.b! Activating new plugins require a certain firmware of the CMe3100, which means that a firmware upgrade is neeeded in order to start use the plugin. If purchasing a CMe3100 including a plugin, the CMe3100 is delivered with the latest firmware and a firmware upgrade is not required.