Only split a given string (e.g., "-abc") into short options (e.g., "-a",
"-b", "-c") if all those are flags. To further avoid mistakenly
transform common arguments, catch "flag provided but not defined" errors
to iteratively transform short options.
Signed-off-by: Valentin Rothberg <vrothberg@suse.com>
Fixes: https://github.com/projectatomic/libpod/issues/714
