manual and smaple code for DFRobotics relay shield 2.1

I asked a friend of me to (help him) to buy a plain 8 port relay for his arduino project.
To my surprise he came back with 2 Arduino compatible shields from DFRobot both are 4 ports. (2 times 4 makes 8 too)
One is the 1.2 version and the other is the 2.1 version.

The 2.1 version is a mystery for me,
Even Google image search doesn't know of its assistance.
I couldn't find any documentation on their site about this product, but based on their forum some people use it too.
So i was hoping maybe someone knows where the manual can be downloaded, and the sample code.

Another thing i note these boards have a power connector, that surprises me a little as a relay board shouldn't use that much power wouldn't an Arduino Uno be enough to power them ?, or is it common that shield boards have a power connector, i never before had the luxury of a real arduino compatible shield.. so i wonder why this is (they didn't put 2 extra DC adapters in.. so i doubt its required).

PS (i asked this question on their site too, but out of experience i know the most advanced arduino engineers are on this site, i think i will have better luck here)

http://arduino-info.wikispaces.com/arduinopower

Might not list your particular board but it explains the relay board genre very well.

You should anticipate that the relays will require ~100ma per relay when energized and that's why they need external power. If you look up the specs for the particular model relay (google the part number) you'll get a more definitive answer.

Thanks handy for the abbreviations written on the board.
But the point is the 2.1 board has some switches, and i like to know their function too.

I asume this board might use some other protocol to switch and those switches might set ID's or something like that.