Open
Description
As discussed in #20899, in addition to Sys.BINDIR (location of julia executable) it would be good to have Sys.LIBDIR (installed location of libjulia), Sys.INCLUDEDIR (installed location of julia.h), and perhaps a few others (e.g. Sys.JULIA and Sys.LIBJULIA for the full paths of julia and libjulia, respectively).