Add keepIf proc and keepIfIt template to sequtils
Add keepIf proc and keepIfIt template to sequtils

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