Move YARN-4519 in CHANGES.txt to 2.8
Move YARN-4519 in CHANGES.txt to 2.8

JingchengDu/hadoop,bitmybytes/hadoop,GeLiXin/hadoop,WIgor/hadoop,ctrezzo/hadoop,WIgor/hadoop,lukmajercak/hadoop,ctrezzo/hadoop,Ethanlm/hadoop,wenxinhe/hadoop,ChetnaChaudhari/hadoop,littlezhou/hadoop,steveloughran/hadoop,bitmybytes/hadoop,JingchengDu/hadoop,Ethanlm/hadoop,ucare-uchicago/hadoop,legend-hua/hadoop,dierobotsdie/hadoop,979969786/hadoop,huafengw/hadoop,ucare-uchicago/hadoop,wenxinhe/hadoop,dennishuo/hadoop,lukmajercak/hadoop,apache/hadoop,979969786/hadoop,huafengw/hadoop,plusplusjiajia/hadoop,Ethanlm/hadoop,apurtell/hadoop,nandakumar131/hadoop,nandakumar131/hadoop,ctrezzo/hadoop,steveloughran/hadoop,nandakumar131/hadoop,wenxinhe/hadoop,mapr/hadoop-common,huafengw/hadoop,WIgor/hadoop,legend-hua/hadoop,steveloughran/hadoop,wenxinhe/hadoop,legend-hua/hadoop,plusplusjiajia/hadoop,ronny-macmaster/hadoop,soumabrata-chakraborty/hadoop,wwjiang007/hadoop,apurtell/hadoop,JingchengDu/hadoop,979969786/hadoop,apache/hadoop,huafengw/hadoop,littlezhou/hadoop,lukmajercak/hadoop,979969786/hadoop,legend-hua/hadoop,huafengw/hadoop,ctrezzo/hadoop,Ethanlm/hadoop,apache/hadoop,bitmybytes/hadoop,Ethanlm/hadoop,lukmajercak/hadoop,legend-hua/hadoop,apurtell/hadoop,plusplusjiajia/hadoop,dennishuo/hadoop,bitmybytes/hadoop,JingchengDu/hadoop,ronny-macmaster/hadoop,dennishuo/hadoop,soumabrata-chakraborty/hadoop,mapr/hadoop-common,apurtell/hadoop,wwjiang007/hadoop,dierobotsdie/hadoop,soumabrata-chakraborty/hadoop,dierobotsdie/hadoop,steveloughran/hadoop,ChetnaChaudhari/hadoop,dennishuo/hadoop,979969786/hadoop,szegedim/hadoop,GeLiXin/hadoop,xiao-chen/hadoop,ctrezzo/hadoop,steveloughran/hadoop,dierobotsdie/hadoop,soumabrata-chakraborty/hadoop,plusplusjiajia/hadoop,nandakumar131/hadoop,ChetnaChaudhari/hadoop,littlezhou/hadoop,ChetnaChaudhari/hadoop,apache/hadoop,ucare-uchicago/hadoop,xiao-chen/hadoop,GeLiXin/hadoop,dierobotsdie/hadoop,GeLiXin/hadoop,WIgor/hadoop,WIgor/hadoop,dierobotsdie/hadoop,nandakumar131/hadoop,ronny-macmaster/hadoop,wenxinhe/hadoop,bitmybytes/hadoop,dennishuo/hadoop,wwjiang007/hadoop,WIgor/hadoop,mapr/hadoop-common,huafengw/hadoop,littlezhou/hadoop,littlezhou/hadoop,ucare-uchicago/hadoop,wenxinhe/hadoop,apurtell/hadoop,wenxinhe/hadoop,plusplusjiajia/hadoop,bitmybytes/hadoop,ctrezzo/hadoop,GeLiXin/hadoop,wwjiang007/hadoop,979969786/hadoop,steveloughran/hadoop,szegedim/hadoop,wwjiang007/hadoop,steveloughran/hadoop,GeLiXin/hadoop,lukmajercak/hadoop,ronny-macmaster/hadoop,ronny-macmaster/hadoop,szegedim/hadoop,plusplusjiajia/hadoop,szegedim/hadoop,ChetnaChaudhari/hadoop,GeLiXin/hadoop,mapr/hadoop-common,ucare-uchicago/hadoop,xiao-chen/hadoop,xiao-chen/hadoop,ronny-macmaster/hadoop,WIgor/hadoop,apache/hadoop,soumabrata-chakraborty/hadoop,JingchengDu/hadoop,mapr/hadoop-common,nandakumar131/hadoop,apurtell/hadoop,plusplusjiajia/hadoop,lukmajercak/hadoop,mapr/hadoop-common,legend-hua/hadoop,979969786/hadoop,apache/hadoop,mapr/hadoop-common,ronny-macmaster/hadoop,JingchengDu/hadoop,soumabrata-chakraborty/hadoop,xiao-chen/hadoop,ctrezzo/hadoop,Ethanlm/hadoop,dennishuo/hadoop,soumabrata-chakraborty/hadoop,apache/hadoop,xiao-chen/hadoop,JingchengDu/hadoop,ChetnaChaudhari/hadoop,legend-hua/hadoop,dierobotsdie/hadoop,ucare-uchicago/hadoop,lukmajercak/hadoop,szegedim/hadoop,huafengw/hadoop,littlezhou/hadoop,nandakumar131/hadoop,wwjiang007/hadoop,apurtell/hadoop,szegedim/hadoop,dennishuo/hadoop,ucare-uchicago/hadoop,bitmybytes/hadoop,szegedim/hadoop,littlezhou/hadoop,xiao-chen/hadoop,wwjiang007/hadoop,Ethanlm/hadoop,ChetnaChaudhari/hadoop