Extended the "Rderived" library to include linpack fortran functions required to run b25.matcal-5 benchmark (enabled the benchmark in the suite).

Added linux version of the library containing fft implementation. Added b25.matfunc-1 benchmark computing fft, as well as two matcal benchmark that are currently supported,  to the benchmark suite.

refactor RFFI, add 'native' project with Lapack shared libs; add La_rg and misc functions for eigen; implement R_PROFILE_SITE/R_PROFILE_USER evaluation on startup