The CUDA Toolkit's VS integration provides abstractions for host
compiler options for `nvcc` to pass through `-Xcompiler` to the host
MSVC. Populate our secondary flag table and use it to remove flags from
the `AdditionalCompilerOptions` in favor of their abstractions.
Unfortunately a bug in the CUDA 8.0 VS integration prevents us from
passing anything in `AdditionalCompilerOptions` reliably. After taking
out the flags that have dedicated abstractions, drop the rest.
The CUDA Toolkit's VS integration defines abstractions for both options
to `nvcc` and options to pass through `-Xcompiler` to the host MSVC.
We need a separate flag table to parse each set of flags into the
corresponding abstractions. Add empty placeholders for these tables.
Brad King