Metadata optimizations

Building on https://github.com/TauLabs/TauLabs/pull/356, this optimizes update rates for sensor calibration, transmitter calibration, and HiTL simulation.

All functions tested and perform as expected. This includes canceling out of the whatever task is manipulating the metadata (Note, the transmitter functionality was not tested through to the very end, because without a transmitter I couldn't reach the last few pages. I'll do the full transmitter test tomorrow.)

The calibration gains make leveling, six-point, and variance tests 2.5 times faster. The transmitter calibration gains will be harder to see, but I also solved a bug in the calibration process that left the user waiting in one of the wizard pages. Lastly, the increased HiTL telemetry rates will reduce setup efforts required for doing high-accuracy simulations.