luasocket: finish the makefile and add samples

Note: mime.core requires socket.core, and have the same names
this is not compatible with Android, which try to load the same
lib on mime.core load. So, add mime.c in socket.core, mime.core
is also the same lib, for script requiere compatibility

Signed-off-by: Tanguy Pruvot <tanguy.pruvot@gmail.com>