fixing Lua52 incompatibility
fixing Lua52 incompatibility

lukasc-ch/nn,vgire/nn,jonathantompson/nn,caldweln/nn,nicholas-leonard/nn,PraveerSINGH/nn,mlosch/nn,sagarwaghmare69/nn,apaszke/nn,diz-vara/nn,elbamos/nn,colesbury/nn,Moodstocks/nn,witgo/nn,kmul00/nn,andreaskoepf/nn,jhjin/nn,xianjiec/nn,joeyhng/nn,eriche2016/nn