Sample automatic uploader (shell script based simple UI)

The mental Model of a programmer script:

Press 'P':
    Enters the firmware directory.
    If git exists, it pulls the latest firmware. 
Press 's':
    Presents users a list of available serial / upload ports. 
    Select 1
Press 'u':
      It uploads the code based on the arduino-cli comamnd in 
      the script which uses the fuses and other info as mentioned 
      in the programmer_settings.yaml