Change empty callback into nil
Change empty callback into nil

dom96/Nim,judofyr/Nim,endragor/Nim,singularperturbation/Nim,haiodo/Nim,jsanjuas/Nim,dom96/Nim,JCavallo/Nim,judofyr/Nim,reactormonk/nim,gokr/Nim,bvssvni/Nim,zachaysan/Nim,douglas-larocca/Nim,haiodo/Nim,JCavallo/Nim,gokr/Nim,SSPkrolik/Nim,Salafit/Nim,nafsaka/Nim,nanoant/Nim,sferik/Nim,MrJohz/Nim,kirbyfan64/Nim,endragor/Nim,nimLuckyBull/Nim,sarvex/Nim-lang,jfhg/Nim,haiodo/Nim,greyanubis/Nim,fredericksilva/Nim,nimLuckyBull/Nim,jfhg/Nim,endragor/Nim,Salafit/Nim,dom96/Nim,zachaysan/Nim,tmm1/Nim,russpowers/Nim,judofyr/Nim,nafsaka/Nim,tulayang/Nim,reactormonk/nim,jsanjuas/Nim,fmamud/Nim,sferik/Nim,nafsaka/Nim,sarvex/Nim-lang,nafsaka/Nim,fmamud/Nim,nafsaka/Nim,SSPkrolik/Nim,singularperturbation/Nim,Salafit/Nim,Salafit/Nim,Senketsu/Nim,xland/Nim,mbaulch/Nim,jfhg/Nim,jfhg/Nim,Matt14916/Nim,greyanubis/Nim,zachaysan/Nim,MrJohz/Nim,zachaysan/Nim,BlaXpirit/nim,Senketsu/Nim,tulayang/Nim,reactormonk/nim,fredericksilva/Nim,sarvex/Nim-lang,BlaXpirit/nim,nimLuckyBull/Nim,jsanjuas/Nim,kirbyfan64/Nim,jfhg/Nim,Dhertz/Nim,tmm1/Nim,nanoant/Nim,jsanjuas/Nim,reactormonk/nim,gokr/Nim,zachaysan/Nim,gokr/Nim,xland/Nim,xland/Nim,russpowers/Nim,Salafit/Nim,zachaysan/Nim,gokr/Nim,sarvex/Nim-lang,kirbyfan64/Nim,dom96/Nim,kirbyfan64/Nim,msmith491/Nim,msmith491/Nim,BlaXpirit/nim,nimLuckyBull/Nim,SSPkrolik/Nim,tmm1/Nim,sarvex/Nim-lang,fredericksilva/Nim,bvssvni/Nim,douglas-larocca/Nim,Matt14916/Nim,reactormonk/nim,SSPkrolik/Nim,endragor/Nim,fmamud/Nim,gokr/Nim,jsanjuas/Nim,SSPkrolik/Nim,msmith491/Nim,bvssvni/Nim,dom96/Nim,MrJohz/Nim,singularperturbation/Nim,Matt14916/Nim,douglas-larocca/Nim,russpowers/Nim,douglas-larocca/Nim,fmamud/Nim,kirbyfan64/Nim,BlaXpirit/nim,xland/Nim,jsanjuas/Nim,kirbyfan64/Nim,MrJohz/Nim,BlaXpirit/nim,russpowers/Nim,BlaXpirit/nim,fredericksilva/Nim,Dhertz/Nim,Senketsu/Nim,reactormonk/nim,dom96/Nim,Dhertz/Nim,fredericksilva/Nim,mbaulch/Nim,haiodo/Nim,Salafit/Nim,sferik/Nim,SSPkrolik/Nim,haiodo/Nim,kirbyfan64/Nim,MrJohz/Nim,douglas-larocca/Nim,haiodo/Nim,greyanubis/Nim,reactormonk/nim,Dhertz/Nim,endragor/Nim,endragor/Nim,sferik/Nim,nimLuckyBull/Nim,msmith491/Nim,nanoant/Nim,JCavallo/Nim,greyanubis/Nim,fredericksilva/Nim,dom96/Nim,Dhertz/Nim,judofyr/Nim,endragor/Nim,greyanubis/Nim,haiodo/Nim,fmamud/Nim,mbaulch/Nim,tmm1/Nim,russpowers/Nim,JCavallo/Nim,Dhertz/Nim,tmm1/Nim,nanoant/Nim,nafsaka/Nim,douglas-larocca/Nim,Matt14916/Nim,nimLuckyBull/Nim,bvssvni/Nim,JCavallo/Nim,greyanubis/Nim,russpowers/Nim,kirbyfan64/Nim,jfhg/Nim,BlaXpirit/nim,Salafit/Nim,nimLuckyBull/Nim,singularperturbation/Nim,Dhertz/Nim,tmm1/Nim,SSPkrolik/Nim,sferik/Nim,tulayang/Nim,sarvex/Nim-lang,greyanubis/Nim,tulayang/Nim,gokr/Nim,tmm1/Nim,gokr/Nim,bvssvni/Nim,sferik/Nim,SSPkrolik/Nim,Senketsu/Nim,judofyr/Nim,tulayang/Nim,sarvex/Nim-lang,sferik/Nim,Matt14916/Nim,judofyr/Nim,judofyr/Nim,sferik/Nim,nafsaka/Nim,singularperturbation/Nim,MrJohz/Nim,fmamud/Nim,jfhg/Nim,douglas-larocca/Nim,Matt14916/Nim,douglas-larocca/Nim,singularperturbation/Nim,bvssvni/Nim,msmith491/Nim,Matt14916/Nim,mbaulch/Nim,mbaulch/Nim,Senketsu/Nim,xland/Nim,xland/Nim,zachaysan/Nim,fredericksilva/Nim,tulayang/Nim,singularperturbation/Nim,mbaulch/Nim,JCavallo/Nim,mbaulch/Nim,russpowers/Nim,xland/Nim,JCavallo/Nim,fredericksilva/Nim,fmamud/Nim,Senketsu/Nim,msmith491/Nim,reactormonk/nim,nanoant/Nim,Senketsu/Nim,jsanjuas/Nim,BlaXpirit/nim,nanoant/Nim,MrJohz/Nim,bvssvni/Nim,judofyr/Nim,msmith491/Nim,nanoant/Nim