Convert (cOldPsw,LenField,lScramble) --> cNewPassword:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Functions:
~~~~~~~~~~
Encryption or decryption (according of the lScramble value) of cOldPsw
password variable, with ascii character simple shift. The return value
length is set to LenField.

Parameter description:
~~~~~~~~~~~~~~~~~~~~~~
cOldPsw:   Text string for decryption.
LenField:  Decrypted string length.
lScramble: True if to decrypt, false if to encrypt.

Return value:
~~~~~~~~~~~~~
Decrypted/encrypted text string.

Source code is in file  c_dbf.prg.