[HOT] OSM Tasking Manager: OSM Wiki

[MarkS]

I thought it would be usefuly to have somewhere where we have 
instructions for how to use the OSM Tasking Manager and what we mean by 
doing and validating a task so I've started a page on the wiki: 
http://wiki.openstreetmap.org/wiki/OSM_Tasking_Manager

As this is a first version of the page I've noted down what I think 
doing and validating mean. But if somebody has more knowledge in this 
area then please feel free to fix it.