Merge branch 'dl/complete-stash-updates'

Further update the command line completion (in contrib/) for "git stash". * dl/complete-stash-updates: git-completion.bash: consolidate cases in _git_stash() git-completion.bash: use $__git_cmd_idx in more places git-completion.bash: rename to $__git_cmd_idx git-completion.bash: separate some commands onto their own line