[cat-interop] hello world cartalogue

[Paul van Genuchten]

Hi all, inspired by last weeks event I decided to put online a prototype 
I did last summer (Bolsena CodeSprint) of a mobile catalogue client 
(http://gnmobile.genuchten.net)
I hope this can be inspiring for some of you to get some new ideas on 
catalogue usage
or maybe add some code (or feature/requests/issues) to get the thing 
matured, pull requests welcome :-)
I got some good comments already, for example from teachers who like 
their students to use it in the field

Code is at: https://github.com/pvgenuchten/cartalogue

Cheers, Paul