Introduction about rumpkernel

Hi folks,

There it is the new BSDMag issue alongside with a complete article about using sudo, my article about using rumpkernel in a Xen context. I had this topic in mind since quite lot of months and that was still totally unknown to me until recently. I did not spend the time I expected to in first place but if it produces enough attraction, I may talk about it again in the future ;-)

Ah, also short note, nginx and DeviceAtlas APIs work well in this environment (some folks before me tested already nginx alone like here) so if you prefer using all of this in this secure environment, there is no issue ;-)