Import luabins 831869cdc8c5e7579804e6472a2dc6cbe0b2672b
Integrate luabins into Aegisub's build system

Make it build as C++ so it links properly against the C++-built version
of Lua used in Aegisub too.
Load luabins library into Auto4 Lua environment
Use lua_pushlstring() so strings with embedded NULs also work
Work around boost::format bug

See https://svn.boost.org/trac/boost/ticket/9360
It seems that the %X specifier is ignored if the input value is a char type
and the char is instead output verbatim and not in its integer value.
Casting it to an int works around this.
Fix bug in extradata id list reading