install bash-completion (#118)

from what I can tell, our recent problems with bash-completion was not due to a misconfiguration. It's simply due to the package not existing on our box. so this install should do the trick.

scripts/provision.sh

@@ -45,7 +45,7 @@ apt-get update
 
 apt-get install -y build-essential dos2unix gcc git libmcrypt4 libpcre3-dev ntp unzip \
 make python2.7-dev python-pip re2c supervisor unattended-upgrades whois vim libnotify-bin \
-pv cifs-utils mcrypt
+pv cifs-utils mcrypt bash-completion
 
 # Set My Timezone