Change over Printer_GetDeviceID() to require a pointer to the destination buffer plus the buffer size, rather than using a pointer to a special structure.
Make new Printer_SendData() function to hide the implementation of sending data to an attached printer, cleaning up the main demo source file body.
Seperated out Lib components of the incomplete BluetoothHost demo application out into a seperate Lib subfolder.
Changed F_CLOCK entries in project makefiles to alias to F_CPU by default, as this is the most common case.