kokkos branch will not compile with a pre-installed kokkos library

[naromero77]

It should be possible to do something like:
cmake -DKOKKOS_INCLUDES=<foo> -DKOKKOS_LIBRARIES=<bar> ...

or

alternatively
cmake -DKOKKOS_INSTALL_PATH=<foobar> ...

And the kokkos branch of miniqmc will build with a pre-installed kokkos library.

I hacked in @rcclay suggestion from the miniqmc slack channel, but this causes another error: Kokkos then complains about a lack of an OpenMP flag. If you manually add the -fopenmp flag, then you get a hard error from KOKKOS_INLINE.