Merge branch 'bk/complete-bisect'

Command line completion support (in contrib/) has been updated for "git bisect". * bk/complete-bisect: completion: bisect: recognize but do not complete view subcommand completion: bisect: complete log opts for visualize subcommand completion: new function __git_complete_log_opts completion: bisect: complete missing --first-parent and - -no-checkout options completion: bisect: complete custom terms and related options completion: bisect: complete bad, new, old, and help subcommands completion: tests: always use 'master' for default initial branch name