disable tautolgical compare warning in clang
disable tautolgical compare warning in clang

disable the tautological compare warning as it is triggered by crypto++ using
unsigned ints in comparisons to zero in template code. crypto++ do not show
any indication of fixing it.

this commit does add a dependency on grep but that should not be a major
problem

Schwertspize/cuberite,jammet/MCServer,linnemannr/MCServer,Fighter19/cuberite,marvinkopf/cuberite,Haxi52/cuberite,ionux/MCServer,HelenaKitty/EbooMC,mjssw/cuberite,mmdk95/cuberite,nichwall/cuberite,Howaner/MCServer,nevercast/cuberite,johnsoch/cuberite,Haxi52/cuberite,Frownigami1/cuberite,zackp30/cuberite,Haxi52/cuberite,ionux/MCServer,zackp30/cuberite,marvinkopf/cuberite,thetaeo/cuberite,guijun/MCServer,birkett/cuberite,thetaeo/cuberite,nichwall/cuberite,guijun/MCServer,Altenius/cuberite,birkett/MCServer,birkett/MCServer,Tri125/MCServer,SamOatesPlugins/cuberite,mc-server/MCServer,zackp30/cuberite,Altenius/cuberite,birkett/MCServer,mc-server/MCServer,nicodinh/cuberite,birkett/cuberite,Frownigami1/cuberite,bendl/cuberite,HelenaKitty/EbooMC,mjssw/cuberite,nevercast/cuberite,guijun/MCServer,QUSpilPrgm/cuberite,MuhammadWang/MCServer,electromatter/cuberite,electromatter/cuberite,ionux/MCServer,mmdk95/cuberite,johnsoch/cuberite,marvinkopf/cuberite,thetaeo/cuberite,Schwertspize/cuberite,Schwertspize/cuberite,Altenius/cuberite,kevinr/cuberite,thetaeo/cuberite,thetaeo/cuberite,kevinr/cuberite,Haxi52/cuberite,electromatter/cuberite,QUSpilPrgm/cuberite,Frownigami1/cuberite,mmdk95/cuberite,nichwall/cuberite,linnemannr/MCServer,tonibm19/cuberite,jammet/MCServer,linnemannr/MCServer,Fighter19/cuberite,nichwall/cuberite,ionux/MCServer,jammet/MCServer,bendl/cuberite,electromatter/cuberite,kevinr/cuberite,tonibm19/cuberite,mmdk95/cuberite,Altenius/cuberite,johnsoch/cuberite,nounoursheureux/MCServer,QUSpilPrgm/cuberite,Frownigami1/cuberite,Tri125/MCServer,marvinkopf/cuberite,guijun/MCServer,marvinkopf/cuberite,HelenaKitty/EbooMC,nounoursheureux/MCServer,Fighter19/cuberite,Frownigami1/cuberite,jammet/MCServer,nichwall/cuberite,nicodinh/cuberite,nicodinh/cuberite,mc-server/MCServer,zackp30/cuberite,kevinr/cuberite,MuhammadWang/MCServer,mjssw/cuberite,nounoursheureux/MCServer,zackp30/cuberite,birkett/MCServer,kevinr/cuberite,Fighter19/cuberite,MuhammadWang/MCServer,birkett/cuberite,guijun/MCServer,nichwall/cuberite,jammet/MCServer,bendl/cuberite,nevercast/cuberite,Haxi52/cuberite,Schwertspize/cuberite,Howaner/MCServer,linnemannr/MCServer,Howaner/MCServer,birkett/MCServer,mmdk95/cuberite,Tri125/MCServer,kevinr/cuberite,jammet/MCServer,Howaner/MCServer,nounoursheureux/MCServer,tonibm19/cuberite,mmdk95/cuberite,Fighter19/cuberite,nounoursheureux/MCServer,Altenius/cuberite,tonibm19/cuberite,birkett/cuberite,marvinkopf/cuberite,mjssw/cuberite,nevercast/cuberite,guijun/MCServer,nevercast/cuberite,mc-server/MCServer,QUSpilPrgm/cuberite,Haxi52/cuberite,QUSpilPrgm/cuberite,thetaeo/cuberite,nevercast/cuberite,nounoursheureux/MCServer,mc-server/MCServer,Schwertspize/cuberite,QUSpilPrgm/cuberite,ionux/MCServer,zackp30/cuberite,electromatter/cuberite,electromatter/cuberite,Howaner/MCServer,MuhammadWang/MCServer,linnemannr/MCServer,nicodinh/cuberite,SamOatesPlugins/cuberite,johnsoch/cuberite,Tri125/MCServer,birkett/MCServer,mc-server/MCServer,Fighter19/cuberite,bendl/cuberite,nicodinh/cuberite,SamOatesPlugins/cuberite,mjssw/cuberite,linnemannr/MCServer,Howaner/MCServer,ionux/MCServer,Tri125/MCServer,birkett/cuberite,nicodinh/cuberite,SamOatesPlugins/cuberite,MuhammadWang/MCServer,birkett/cuberite,Tri125/MCServer,mjssw/cuberite,tonibm19/cuberite,HelenaKitty/EbooMC,HelenaKitty/EbooMC,tonibm19/cuberite,bendl/cuberite,SamOatesPlugins/cuberite,johnsoch/cuberite