Add support for crypted passwords to password lookup

Added new parameter 'encrypt' with same semantics from that of
vars_prompt. When encryption is requested a random salt will be
generated and stored along the password in the form:
'\<password\> salt=\<salt\>'.

Also store password with an ending '\n' for easier looking at files
with console tools. File content was being already rstripped so this
is harmless.

Includes a fix for Javier's name following his request.