Wrong help for sqlmigrate management command

[Dmitri Bogomolov]

sqlmigrate probably should have the same help message as migrate. Compare:

# python manage.py help migrate
Usage: manage.py migrate [options] [app_label] [migration_name]
...

# python manage.py help sqlmigrate
Usage: manage.py sqlmigrate [options]
...

Otherwise, it produces obscure error:

# python manage.py sqlmigrate --database=database1
CommandError: Wrong number of arguments (expecting 'sqlmigrate app_label migrationname')

[Claude Paroz]

This is an 1.7-only issue, as in master, the argparse version of the command does show required arguments.

[Claude Paroz <claude@…>]

In 31309d4722aa5e08d10733f8cf36d3184799044b:

[1.7.x] Fixed #23478 -- Complemented sqlmigrate command help