Checking user input in case qhull is not found by cmake
Checking user input in case qhull is not found by cmake

git-svn-id: 5398946ba177a3e438c2dae55e2cdfc2fb96c905@1196 a9d63959-f2ad-4865-b262-bf0e56cfafb6

mschoeler/pcl,RufaelDev/pcc-mp3dg,MMiknis/pcl,raydtang/pcl,KevenRing/pcl,damienjadeduff/pcl,pkuhto/pcl,chenxingzhe/pcl,shivmalhotra/pcl,mschoeler/pcl,shivmalhotra/pcl,wgapl/pcl,kanster/pcl,srbhprajapati/pcl,drmateo/pcl,closerbibi/pcl,mikhail-matrosov/pcl,ResByte/pcl,sbec/pcl,KevenRing/vlp,simonleonard/pcl,ResByte/pcl,soulsheng/pcl,chenxingzhe/pcl,krips89/pcl_newfeatures,msalvato/pcl_kinfu_highres,locnx1984/pcl,shivmalhotra/pcl,stfuchs/pcl,Tabjones/pcl,drmateo/pcl,msalvato/pcl_kinfu_highres,mikhail-matrosov/pcl,stfuchs/pcl,ipa-rmb/pcl,3dtof/pcl,jeppewalther/kinfu_segmentation,the-glu/pcl,shivmalhotra/pcl,v4hn/pcl,fskuka/pcl,ipa-rmb/pcl,LZRS/pcl,wgapl/pcl,srbhprajapati/pcl,stfuchs/pcl,starius/pcl,mikhail-matrosov/pcl,shangwuhencc/pcl,locnx1984/pcl,raydtang/pcl,locnx1984/pcl,jakobwilm/pcl,LZRS/pcl,jakobwilm/pcl,fskuka/pcl,mschoeler/pcl,zavataafnan/pcl-truck,lebronzhang/pcl,fskuka/pcl,pkuhto/pcl,raydtang/pcl,starius/pcl,msalvato/pcl_kinfu_highres,ResByte/pcl,cascheberg/pcl,v4hn/pcl,jakobwilm/pcl,chatchavan/pcl,nh2/pcl,drmateo/pcl,shangwuhencc/pcl,MMiknis/pcl,zavataafnan/pcl-truck,chenxingzhe/pcl,KevenRing/vlp,lebronzhang/pcl,kanster/pcl,stefanbuettner/pcl,mschoeler/pcl,zhangxaochen/pcl,raydtang/pcl,KevenRing/vlp,fanxiaochen/mypcltest,lydhr/pcl,the-glu/pcl,simonleonard/pcl,ResByte/pcl,Tabjones/pcl,nikste/pcl,ipa-rmb/pcl,soulsheng/pcl,3dtof/pcl,krips89/pcl_newfeatures,fanxiaochen/mypcltest,Tabjones/pcl,zavataafnan/pcl-truck,srbhprajapati/pcl,stefanbuettner/pcl,RufaelDev/pcc-mp3dg,zhangxaochen/pcl,soulsheng/pcl,nikste/pcl,shangwuhencc/pcl,nh2/pcl,zhangxaochen/pcl,stfuchs/pcl,3dtof/pcl,chatchavan/pcl,KevenRing/vlp,krips89/pcl_newfeatures,closerbibi/pcl,sbec/pcl,fanxiaochen/mypcltest,lydhr/pcl,chatchavan/pcl,kanster/pcl,shyamalschandra/pcl,chenxingzhe/pcl,jakobwilm/pcl,zhangxaochen/pcl,Nerei/pcl_old_repo,Tabjones/pcl,sbec/pcl,shyamalschandra/pcl,ResByte/pcl,nh2/pcl,srbhprajapati/pcl,damienjadeduff/pcl,shangwuhencc/pcl,MMiknis/pcl,jakobwilm/pcl,the-glu/pcl,shyamalschandra/pcl,drmateo/pcl,KevenRing/vlp,v4hn/pcl,mschoeler/pcl,fskuka/pcl,DaikiMaekawa/pcl,shyamalschandra/pcl,fanxiaochen/mypcltest,the-glu/pcl,KevenRing/pcl,mikhail-matrosov/pcl,damienjadeduff/pcl,closerbibi/pcl,the-glu/pcl,RufaelDev/pcc-mp3dg,fskuka/pcl,cascheberg/pcl,wgapl/pcl,kanster/pcl,zavataafnan/pcl-truck,LZRS/pcl,pkuhto/pcl,nikste/pcl,starius/pcl,lebronzhang/pcl,MMiknis/pcl,locnx1984/pcl,cascheberg/pcl,shyamalschandra/pcl,chatchavan/pcl,nikste/pcl,damienjadeduff/pcl,closerbibi/pcl,Nerei/pcl_old_repo,mikhail-matrosov/pcl,raydtang/pcl,msalvato/pcl_kinfu_highres,chenxingzhe/pcl,stefanbuettner/pcl,jeppewalther/kinfu_segmentation,jeppewalther/kinfu_segmentation,lydhr/pcl,zhangxaochen/pcl,damienjadeduff/pcl,ipa-rmb/pcl,drmateo/pcl,MMiknis/pcl,nh2/pcl,krips89/pcl_newfeatures,nikste/pcl,krips89/pcl_newfeatures,kanster/pcl,cascheberg/pcl,DaikiMaekawa/pcl,soulsheng/pcl,closerbibi/pcl,DaikiMaekawa/pcl,lebronzhang/pcl,shangwuhencc/pcl,lebronzhang/pcl,RufaelDev/pcc-mp3dg,3dtof/pcl,RufaelDev/pcc-mp3dg,KevenRing/pcl,stefanbuettner/pcl,zavataafnan/pcl-truck,srbhprajapati/pcl,fanxiaochen/mypcltest,msalvato/pcl_kinfu_highres,Nerei/pcl_old_repo,lydhr/pcl,v4hn/pcl,KevenRing/pcl,LZRS/pcl,simonleonard/pcl,Tabjones/pcl,KevenRing/pcl,3dtof/pcl,LZRS/pcl,stfuchs/pcl,DaikiMaekawa/pcl,starius/pcl,locnx1984/pcl,simonleonard/pcl,Nerei/pcl_old_repo,wgapl/pcl,wgapl/pcl,pkuhto/pcl,lydhr/pcl,cascheberg/pcl,simonleonard/pcl,sbec/pcl,v4hn/pcl,starius/pcl,jeppewalther/kinfu_segmentation,soulsheng/pcl,shivmalhotra/pcl,jeppewalther/kinfu_segmentation,stefanbuettner/pcl,DaikiMaekawa/pcl,ipa-rmb/pcl,sbec/pcl,pkuhto/pcl