Sandcastle generation for inheritdoc in FRC.NetworkTables.Core not working

[ThadHouse]

I'm actually debating just removing all the inheritdoc docs and replacing them with static. Keeping the sandcastle builds maintained to copy the inheritdocs to the XML is a pain, and they really don't give us much benefit. It should be a pretty easy modification in NetworkTables. WPILib will be harder, but it's less of an issue there at least for right now, since we only build for net451.

@jkoritzinsky what do you think?

[jkoritzinsky]

I'm fine with that!