DIET -> Vishnu

Replaced DIET by Vishnu in the code and in some of the documentation files
Externalisation of request now possible, first example with the update with join that does not work the same for mysql and postgresql, so a map containing the request is stored
Fix for restore configuration
Fix with join update problems, all ums automtest are ok on postgre now
Add description of parameters to be replaced for requests
add Sed and client configuration keys for ssl support
add config key for ssl use
Encryptian using public and private key before sending mesaage in zmq socket
add encyptian functionality
encryptian with openSSL
add debuging message
fix encryption algorithm
Added support for basic AES ciphering
more changes

first step with aes encryption

added support for aes ciphering
fixed problem with dbusessl param
first steps towards TLS using openssl
updated error messages
ssl works for one request
added TLS support
first steps adding TLS in the dispatcher