Add libssl-dev for Ubuntu
Add libssl-dev for Ubuntu

Rebuilding pyOpenSSL requires the SSL development libraries. This is
present in files/rpms/general, but was missed in files/apts/general.

Change-Id: Ie3c688e2d74485eb7f981363633bbddab5da7046

thomasem/devstack,avvocatodemarchis/devstack,pombredanne/devstack,noironetworks/devstack,pczerkas/devstack,herrsechs/devstack,group-policy/devstack,bq-xiao/devstack,eshnil2000/devstack,nawawi/openstack,andrewrothstein/devstack,TwinkleChawla/devstack,pczerkas/devstack,j4/devstack,kplus/devstack-moonshot,eharney/devstack,HPCHub/devstack,Mahito/devstack,bswartz/devstack,neerja28/Devstack_GlusterFS,richliu/devstack,affo/devstack,openstack-dev/devstack,sequenceiq/devstack,pacinete/devstack,nawawi/openstack,atulpatil301/devstack,vsham20/devstack,group-policy/devstack,j4/devstack,sequenceiq/devstack,upadhyay-prashant/devstack,costingalan/devstack,bswartz/devstack,vishnugonela/devstack,neerja28/Devstack_GlusterFS,pombredanne/devstack,NaokiMiyata/devstack,ozamiatin/devstack,BSJAIN92/OpenStack,mc2014/devstack,noironetworks/devstack,bljgaurav/openstack-test,bq-xiao/devstack,mc2014/devstack,bljgaurav/openstack-test,parul24/devstack,dirkmueller/devstack,samgoon/devstack,rushiagr/devstack,thomasem/devstack,kplus/devstack-moonshot,promptworks/devstack,andrewrothstein/devstack,LoHChina/devstack,BSJAIN92/OpenStack,bigswitch/devstack,vishnugonela/devstack,ozamiatin/devstack,nuxeh/devstack,varunarya10/devstack,nuxeh/devstack,sc68cal/devstack,vsham20/devstack,avvocatodemarchis/devstack,atulpatil301/devstack,virtualopensystems/devstack,wenhuizhang/devstack,wenhuizhang/devstack,herrsechs/devstack,olivierlemasle/devstack,TwinkleChawla/devstack,flavio-fernandes/devstack,liuquansheng47/devstack,tianweizhang/devstack,liuquansheng47/devstack,tianweizhang/devstack,NaokiMiyata/devstack,costingalan/devstack,dirkmueller/devstack,varunarya10/devstack,rushiagr/devstack,pacinete/devstack,promptworks/devstack,mssumanth/devstack,sc68cal/devstack,parul24/devstack,richliu/devstack,mmasaki/devstack,samgoon/devstack,CloudServer/devstack,dtroyer/devstack,Mahito/devstack,olivierlemasle/devstack,eharney/devstack,bigswitch/devstack,mmasaki/devstack,flavio-fernandes/devstack,dtroyer/devstack,upadhyay-prashant/devstack,affo/devstack,prithivm/branch01,openstack-dev/devstack,prithivm/branch01,mssumanth/devstack,HPCHub/devstack,LoHChina/devstack,CloudServer/devstack