Using 'string' of hexcodes to generate encryption key.
Moved encryption key manipulations to parameters code
Added code to write encryption key to flash
Added feature_encryption to determine when to run init and other encryption code
Added code to allow ATE? and ATE=
Update at header to allow commands up to 36 characters (to allow 32character encryption codes)
     NOTE: Had to change from __pdata to __xdata because not space in PSEG