update firmware filename

changed CC2531ZNP-Pro.hex to CC2531ZNP-Prod.hex 

not sure if changed or typo, but current zip file has the new name

added reset at end of operations.
added option to fix delay multiplier.
added instructions if something go wrong.

* add arguments to allow pin change on command line

* superfluo-eraro korektita en cc_delay

fixed issue #2 «error on page 0: byte 0x00 is 0x00 instead of expected 0x02» due to incorrect write length : we must write entire words to flash.