I know everyone loves digital, but this can also be accomplished with a ramp oscillator and a number of comparators that turn the LEDs on. All you need is a stack of resistors and tap off of each point to get the next comparator level (place these points on the non-inverting input) and those DC levels are compared to the ramp (placed on the inverting input). Transistors to turn the LEDs on are probably not necessary as the comparators can sink the LED current, so all that is needed is a limiting resistor on each LED. A ramp oscillator can be created with the 555 timer (see here: ).
So basically, a 555 timer, two quad comparators and a single comparator (one LED is always on), two transistors (or more preferably a matched pair), and some Rs and Cs should do it.