Show Lua runtime errors during extraction

[systemed]

At present Lua runtime errors encountered during extraction just throw a generic "Lua runtime error".

During contraction, however, the runtime error is reported fully:

if (0 != luaL_dofile(lua_state, profile_path.string().c_str()))
{
    std::cerr << lua_tostring(lua_state, -1) << " occured in scripting block" << std::endl;
    return false;
}

I think OSRM used to show Lua errors during extraction too - I found this code in an old version:

try {
    ...
} catch (const luabind::error &er) {
    std::cerr << er.what() << std::endl;
    lua_State* Ler = er.state();
    report_errors(Ler, -1);
}

...
void BaseParser::report_errors(lua_State *L, const int status) const {
    if( 0!=status ) {
        std::cerr << "-- " << lua_tostring(L, -1) << std::endl;
        lua_pop(L, 1); // remove error message
    }
}

[TheMarex]

Fixed.