Add typing to features and make data types consistent

[duyminh1998]

We should

make the data types that are exported in the features object consistent (from the Lua library that outputs the observations to xml to the FeaturesFromSteam class that parses it)

Because

currently we do not have a consistent agreement of the data types of each field (e.g. an aircraft's heading is a string rather than a float)

Complexity

Easy to medium.

Definition of Done

1. Change the namedtuple objects in features.py to NamedTuple from typing to add typing.
2. Make data types consistent for fields in features.py and pycmo_lib.lua and fix any tests or demos that might be broke.
3. Potentially change SteamClientProps from a data class to a NamedTuple class.