Bugfix: private_fl_print_convert_number() problems and do some cleanup.

Bugfix: private_fl_print_convert_number() problems and do some cleanup.

The private_fl_print_convert_number() function stops either on non-diit, asterisk, or NULL.
The code is subtracting 1 from the string position.
This allows for the subsequent continue and resulting string increment to not overflow the buffer.
The problem happens when the stop position is a non-digit.
This non-digit is effectivly being skipped by this logic.
Change the logic to always return a position that will allow the subsequent increment without modification.
The position at function exit must never be pointing at NULL.
The position at function exit must never be pointing at a non-digit.

Use "++string" instead of "string += 1".

Change the structure to order from 8, 16, 32, 64, and 128.