minor comment change for GREGORIAN/JULIAN calendar
printf/sprintf functionality changed

The file structure of printf/sprintf/fprintf family has canged. We have
split the files in 3 families plus one common base _vsxprintf. The reason
was the fixed buffer size for printf destination string. The changes in
sum are:

1) the _insxxx function have a pointer to a callback function in order to
select the target unctionality. These functionalities are:
   i)  _putc_usr() for user's target stdout defined __putchar() function
  ii)  _putc_dst() for sprintf family destination string array
 iii)  _putc_fil() for fprintf family file output structure.

2) based to (1) printf now has no destination string array.

3) fix the huge float xxxe+xx form value issue.

4) the predefined scheme with PRINTF_TINY/PRINTF_FILES is no longer with
us. RIP #defines...

5) fprintf family is not implemented yet. It will, toggether with the
<file.h> functionality.