====== Covid HW 02 - Processing input data and computing statistics ======
Write a program that:
   * has to have at least one input argument passed on the command line, e.g. ./program_name first_argument
   * displays the first argument and also prints a selection menu to standard output, e.g.
<code>
Welcome! The input parameter is "/dev/ttyACM0"
== program menu ==
Item 1: Control LED
Item 2: Read button state
Item 3: Read joystick
Item 4: Control display
Item c: Enter a custom command
Item e: Exit
Selection:
</code>
   * then the program waits for user input. The program will react just on the allowed options and if wrong selection is made then it prints "Wrong option" to stderr
   * selections 1 to 4 will cause redraw of the menu
   * selection 'c' will allow the user to enter a string which will be printed to the standard output - see the example:
<code>
Welcome! The input paramenter is "/dev/ttyACM0"
== program menu ==
Item 1: Control LED
Item 2: Read button state
Item 3: Read joystick
Item 4: Control display
Item c: Enter a custom command
Item e: Exit
Selection:
</code> 
User input (keyboard) 'c'  - '' denotes character
<code>
Enter commnad: 
</code>
User input (keyboard) "*IDN?" - "" denotes string array
<code>
The command  is "*IDN?"

== program menu ==
Item 1: Control LED
Item 2: Read button state
Item 3: Read joystick
Item 4: Control display
Item c: Enter a custom command
Item e: Exit
Selection:
</code>
   * the program will provide return value TRUE.
   * the program menu will be stored as a global variable as array of strings.
   * the actual number of menu items will be determined by sizeof macro.
   * the printing of the menu will be serviced by a subroutine which will return the selection (represented by ID ) to the calling function through a pointer variable passed as argument.
   * 

These parameters of the program will be evaluated:
  * 1 point - the menu global variable follows requirements.
  * 1 point - the program generates the menu in a loop - all items are working, there is a dedicated function for menu printing and menu selection is saved in a variable passed in as a pointer.
  * 1 point - the program exits with 'e' option properly 
  * 1 point - the program takes an input parameter passed over the command line and prints it for **one time** before all menus
  * 1 point - the program is capable to read a custom command and print the command on the standard output