Make Devices more distinguishable in SMS and prevent duplicted entries

As a user i often have the same Short Name for Similar Devices. To make the same devices types more distinguishable in SMS when looking for a specific device and prevent me to add the same device twice to SMS, the series number seems to be the best attribute. So if i add a series number to the SMS this one should be checked again the exisiting in database and in case it already exists i want to be informed (Warning Messages) that this number is already their. Saving the device basic section without a series number should still be possible but i also should get a hint that the devices could maybe not distinguised to similar devices.

ToDos:

• add the series number to autocompletion backend (backend#155 (closed))
• check in frontend again the exisiting numbers
• add warning in case of already exisiting
• add modal if device is saved without a series number