vppctl: bash completion for vppctl commands

vppctl: bash completion for vppctl commands

Added bash completion that will include all commands from build time
*Script takes list of commands generated by doxygen-siphon-list
*Configured doxygen-siphon makefile to generate just cli commands
*List of cli commands put in /usr/share/vpp
*Stopped siphon using doxygen bootstrap, uses main bootstrap instead
*Added rpm/deb check for installation of packages, separate from bootstrap
*NOTE: Once you have installed the vpp .deb/.rpm package you will have to
 restart bash

Change-Id: Ie503e80d5177481f6e7dbe59378f2e0d76f29152
Signed-off-by: Padraig Connolly <padraig.connolly@intel.com>