Update Ubuntu build instructions from downstream
Update Ubuntu build instructions from downstream

frrp/bitshares,FollowMyVote/bitshares,jakeporter/Bitshares,dacsunlimited/dac_play,bitshares/bitshares,jakeporter/Bitshares,FollowMyVote/bitshares,dacsunlimited/dac_play,bitshares/bitshares,camponez/bitshares,Ziftr/bitshares,FollowMyVote/bitshares,bitshares/devshares,frrp/bitshares,bitsuperlab/cpp-play,FollowMyVote/bitshares,bitsuperlab/cpp-play,camponez/bitshares,dacsunlimited/dac_play,bitshares/bitshares-0.x,jakeporter/Bitshares,jakeporter/Bitshares,bitsuperlab/cpp-play,jakeporter/Bitshares,bitshares/bitshares,bitshares/devshares,camponez/bitshares,bitshares/devshares,bitshares/devshares,Ziftr/bitshares,bitsuperlab/cpp-play,camponez/bitshares,dacsunlimited/dac_play,bitshares/devshares,RemitaBit/Remitabit,jakeporter/Bitshares,bitsuperlab/cpp-play,Ziftr/bitshares,bitshares/bitshares,bitshares/bitshares,RemitaBit/Remitabit,bitshares/bitshares-0.x,RemitaBit/Remitabit,RemitaBit/Remitabit,RemitaBit/Remitabit,Ziftr/bitshares,bitshares/bitshares,bitshares/bitshares-0.x,dacsunlimited/dac_play,frrp/bitshares,RemitaBit/Remitabit,FollowMyVote/bitshares,bitshares/devshares,frrp/bitshares,FollowMyVote/bitshares,bitshares/bitshares-0.x,frrp/bitshares,bitshares/bitshares-0.x,camponez/bitshares,dacsunlimited/dac_play,bitsuperlab/cpp-play,bitshares/bitshares-0.x,frrp/bitshares,camponez/bitshares