Changed link tag to image to show image on the hello world page.
Created nonce struct that holds a key and could generate a nonce
from a remoteAddr string.

The nonce will consist of 128 bits.
32 bit - RemoteAddr in ipv4 format
32 bit - timestamp
32 bit - Global counter increasing for each generation
32 bit - random bits seeded with current timestamp

The nonce is AES encrypted and base64url encoded.
Fix to nonce generation to handle remoteAddr strings with ipv6 format.
Eg. [::1]:58000
Created type Server and added the nonce concept to the server.
New nonce is created with a new server so the global_counter could
be updated each request. Also added so the nut is added to the query
string for each qr code generation.
Added Auth handler to the server package to handle request from Android
client available at https://github.com/geir54/android-sqrl

The implementation only verifies the signature and returns response to
the client to display that the request where successful or not.
Added sample implementation of the AuthHandler using my sqrl package
Added description point about AuthHandler in server implementation.
Merge pull request #1 from kalaspuffar/master

Nonce and AuthHandler