README could be improved by adding a short explanation of "native" usage scenario

[rofl0r]

along the lines of
"if musl-cross is used to create libs for a glibc hostsystem of the same architecture with the intention to run them on the same box,
/lib/ld-musl-$ARCH.so.1 should be created as a symlink to $cross/.../lib/libc.so and /etc/ld-musl-$ARCH.path created with a line containing the $cross libdir"

that's needed to run for example a C++ hello world.