Only takeoff and land command work

[dsadaka]

I know this code hasn't been touched in a couple of years. Perhaps it needs a refresh? No commands other than connect, takeoff and land appear to work.

[blacktm]

Yikes, thanks for the heads up. Will try it out when I get some time, see if I can find the issue. If you see where the bug might be, feel free to send a PR!