Is it possible to control two brakes from a single lever?
Glad to see you're back!

You can use a Problem Solvers Cable Doubler 1:2 to pull 2 brakes with 1 lever. Its a little device which you hook up the two brakes to (assuming they have the same cable pull) with 2 sets of brake cables, then run something to the levers. This works for essentially any pair of cable operated brakes with the same cable pull. 

For hydraulic brakes, there are some lever mounting strategies here, but I'm pretty sure the obvious solution (using a Y-splitter in the hydraulic line) won't work. 

You also might want to look at this question for general one armed cycling stuff. 

As for shifting, a bar end shifter is probably easiest, or shimming a thumb shifter. Depending on how your strength is distributed, an interrupter lever might be useful as well.