Update docs/install.rst
Update docs/install.rst

Added unzip to apt-get required installs
adamlincoln/Bookie,GreenLunar/Bookie,bookieio/Bookie,bookieio/Bookie,GreenLunar/Bookie,pombredanne/Bookie,teodesson/Bookie,GreenLunar/Bookie,charany1/Bookie,charany1/Bookie,adamlincoln/Bookie,skmezanul/Bookie,teodesson/Bookie,wangjun/Bookie,bookieio/Bookie,skmezanul/Bookie,pombredanne/Bookie,bookieio/Bookie,wangjun/Bookie,pombredanne/Bookie,teodesson/Bookie,wangjun/Bookie,charany1/Bookie,skmezanul/Bookie,wangjun/Bookie,adamlincoln/Bookie,GreenLunar/Bookie,teodesson/Bookie,skmezanul/Bookie,adamlincoln/Bookie