[BIOSAL] Minimal build of thorium actor applications

[Boisvert, Sebastien]

Following George's request, I added some options to do minimal builds:

"-lrt" is no longer needed, there is a fallback path with gettimeofday.

For MPI, I had to add "mock_transport" which only sets the rank to 0 and the size to 1.

    The new minimal build only needs libm, libc, and libpthread.
    
    linux-vdso and ld-linux-x86-64 are specific to the Linux operating system
    and/or to the architecture. vdso (vsyscall) is used to invoke some system
    calls directly from userspace for better performance. ld-linux is used
    to load shared libraries.
    
    $ make -j CONFIG_CLOCK_GETTIME=n CONFIG_MPI=n CONFIG_ZLIB=n CC=cc
    $ ldd performance/latency_probe/latency_probe
            linux-vdso.so.1 =>  (0x00007fffc7bff000)
            libm.so.6 => /lib64/libm.so.6 (0x0000003f19a00000)
            libpthread.so.0 => /lib64/libpthread.so.0 (0x0000003f1a200000)
            libc.so.6 => /lib64/libc.so.6 (0x0000003f19600000)
            /lib64/ld-linux-x86-64.so.2 (0x0000003f19200000)
    

That should be easier like this to build on POWER7 or on k1om (or in Eclipse).

George:

You will need to add the makefile options CONFIG_CLOCK_GETTIME=n CONFIG_MPI=n CONFIG_ZLIB=n CC=cc
in Eclipse I think.