It has an HD44780 controller so the standard LiquidCrystal library will work once you have the pins figured out.
That library is designed for the standard 14 pin LCD controller interface and many displays have two more pins for the backlight.
Since you have 15 pins instead of the normal 14 (without backlight) or 16 (with backlight) I suspect that they may be using pin 1 for both GND and the backlight (-) which would normally be on pin 16. You will have to do some experimenting or trace following to check this out. You might get more help if you provide an in-focus picture of the front of your board.
If my assumption is correct then pins 1-14 should work when used with the LCD tutorial --> http://arduino.cc/en/Tutorial/LiquidCrystal. You will have to use the pin numbers rather than just the picture to hook things up.
AARRGGHH -- I see that they have changed the picture and they have cleverly chosen an almost invisible white wire for the RS connection. Make sure you enlarge the picture to see the wire.