[FEA] Support adding additional compile flags in nvrtc.compile

[isVoid]

Is your feature request related to a problem? Please describe.
Currently nvrtc.compile only accepts src, name, cc as input arguments. When we compile a CUDA source. we may want to configure additional compile flags such as -include. To enhance the capability. We should make Numba's nvrtc binding to be more configurable when we need to compile additional feature with Numba.

Describe the solution you'd like
I think there are multiple ways we can achieve this:

• The most straight forward way is to augment the argument list to also accept **options, and append to the existing option list. But it may take multiple layers of exposing to make it available to the dispatcher, and maybe it's not the most preferable UX too.
• Via environment variable. Expose the additional includes via NUMBA_CUDA_RTC_INCLUDE_PATHS environment variable. This makes Numba-cuda easier to adapt under different setup configuration. But may require better documentation on how it should be set.