When "git cmd -h" shows more than one line of usage text (e.g.
the cmd subcommand may take sub-sub-command), parse-options API
learned to align these lines, even across i18n/l10n.
* ab/align-parse-options-help:
parse-options: properly align continued usage output
git rev-parse --parseopt tests: add more usagestr tests
send-pack: properly use parse_options() API for usage string
parse-options API users: align usage output in C-strings