ESC status feedback

Publishing ESC status data to the ORB topic `esc_status`.

Assuming the following units of measurement:
* esc_voltage - 100mV per LSB
* esc_temperature - 0.1 degC per LSB
> Floating point constants are preferred lowercase.

Do you mean the F suffix in the floating point literal? (I don't see a constant here)

> The static cast is redundant when multiplying with a floating point value and should be avoided (because it makes assumptions about the type of msg.temperature1, instead of letting the automatic type conversion do the right thing)

Is it a local convention? MISRA C++ 2008 says this:

> Rule 5–0–5 There shall be no implicit floating-integral conversions. [Undefined 4.9(1)]
> Conversions from floating point to integral types discard information, and may lead to undefined behaviour if the floating-point value cannot be represented in the integral type.
> Conversions from integral types to floating point types may not result in an exact representation, which may not be consistent with developer expectations.

This can be enforced with `-Wconversion`.