Added some advice on upgrading
Added some advice on upgrading

rnveach/checkstyle,jonmbake/checkstyle,Bhavik3/checkstyle,cs1331/checkstyle,sirdis/checkstyle,sabaka/checkstyle,StetsiukRoman/checkstyle,sharang108/checkstyle,WilliamRen/checkstyle,romani/checkstyle,AkshitaKukreja30/checkstyle,checkstyle/checkstyle,another-dave/checkstyle,sharang108/checkstyle,jochenvdv/checkstyle,vboerchers/checkstyle,philwebb/checkstyle,MEZk/checkstyle,jasonchaffee/checkstyle,llocc/checkstyle,attatrol/checkstyle,pietern/checkstyle,checkstyle/checkstyle,jdoyle65/checkstyle,sirdis/checkstyle,FeodorFitsner/checkstyle,naver/checkstyle,universsky/checkstyle,Godin/checkstyle,naver/checkstyle,romani/checkstyle,AkshitaKukreja30/checkstyle,pbaranchikov/checkstyle,vboerchers/checkstyle,zofuthan/checkstyle-1,sirdis/checkstyle,nikhilgupta23/checkstyle,liscju/checkstyle,izishared/checkstyle,rnveach/checkstyle,izishared/checkstyle,beckerhd/checkstyle,rmswimkktt/checkstyle,zofuthan/checkstyle-1,StetsiukRoman/checkstyle,pbaranchikov/checkstyle,cs1331/checkstyle,sabaka/checkstyle,llocc/checkstyle,gallandarakhneorg/checkstyle,philwebb/checkstyle,universsky/checkstyle,romani/checkstyle,rnveach/checkstyle,designreuse/checkstyle,gallandarakhneorg/checkstyle,FeodorFitsner/checkstyle,izishared/checkstyle,jasonchaffee/checkstyle,mkordas/checkstyle,MEZk/checkstyle,mkordas/checkstyle,gallandarakhneorg/checkstyle,philwebb/checkstyle,checkstyle/checkstyle,bansalayush/checkstyle,WonderCsabo/checkstyle,FeodorFitsner/checkstyle,ivanov-alex/checkstyle,rnveach/checkstyle,StetsiukRoman/checkstyle,checkstyle/checkstyle,designreuse/checkstyle,pietern/checkstyle,attatrol/checkstyle,HubSpot/checkstyle,designreuse/checkstyle,rnveach/checkstyle,universsky/checkstyle,vboerchers/checkstyle,liscju/checkstyle,Godin/checkstyle,rnveach/checkstyle,HubSpot/checkstyle,autermann/checkstyle,liscju/checkstyle,checkstyle/checkstyle,jonmbake/checkstyle,ilanKeshet/checkstyle,Andrew0701/checkstyle,beckerhd/checkstyle,beckerhd/checkstyle,mkordas/checkstyle,romani/checkstyle,pietern/checkstyle,Bhavik3/checkstyle,nikhilgupta23/checkstyle,cs1331/checkstyle,HubSpot/checkstyle,bansalayush/checkstyle,checkstyle/checkstyle,sharang108/checkstyle,WonderCsabo/checkstyle,Godin/checkstyle,ilanKeshet/checkstyle,WilliamRen/checkstyle,baratali/checkstyle,zofuthan/checkstyle-1,Andrew0701/checkstyle,WilliamRen/checkstyle,another-dave/checkstyle,rmswimkktt/checkstyle,baratali/checkstyle,jasonchaffee/checkstyle,ivanov-alex/checkstyle,rmswimkktt/checkstyle,jonmbake/checkstyle,autermann/checkstyle,ivanov-alex/checkstyle,Bhavik3/checkstyle,WonderCsabo/checkstyle,jochenvdv/checkstyle,baratali/checkstyle,jdoyle65/checkstyle,AkshitaKukreja30/checkstyle,jochenvdv/checkstyle,attatrol/checkstyle,MEZk/checkstyle,another-dave/checkstyle,naver/checkstyle,ilanKeshet/checkstyle,romani/checkstyle,romani/checkstyle,nikhilgupta23/checkstyle,sabaka/checkstyle,autermann/checkstyle,llocc/checkstyle,bansalayush/checkstyle