Update Readme.md

# docker-entrypoint Usage

```

docker run -it --rm esgfhub/slcs-server

usage: docker-entrypoint.py [-h] -sn my-node.esgf.org -ds another -su

                            http://my-cdn.esgf.org/slcs-static/

                            [-up slcs-admin] [-xf] -sdn esgf_slcs_server -sdu

                            db_user -sdh slcsdb.esgf.org [-sdp 5432]

                            [-sde django.db.backends.postgresql] -udn

                            esgf_slcs_server -udu db_user -udh slcsdb.esgf.org

                            [-udt user] [-uds esgf_security] [-udp 5432]

                            [-ude django.db.backends.postgresql]

                            [-se no-reply@my-node.esgf.org]

                            [-ccf /usr/local/esgf-slcs-server/conf/ca/08bd99c7.0 [/usr/local/esgf-slcs-server/conf/ca/08bd99c7.0 ...]]

                            [-dd]

                            [-da John Doe,john@example.com [Mary,mary@example.com ...]]

Start an ESGF SLCS instance.

optional arguments:

  -h, --help            show this help message and exit

  -sn my-node.esgf.org, --server-name my-node.esgf.org

                        The Fully Qualified Domain Name of the SLCS server.

                        (default: None)

  -ds another, --django-superuser another

                        The user in UserDB that should be given django

                        superuser permissions. (default: None)

  -su http://my-cdn.esgf.org/slcs-static/, --static-url http://my-cdn.esgf.org/slcs-static/

                        The URL used when retrieving static files. (default:

                        None)

  -se no-reply@my-node.esgf.org, --server-email no-reply@my-node.esgf.org

                        The email address used when sending emails. Defaults

                        to no-reply@[--server-name]. (default: None)

  -ccf /usr/local/esgf-slcs-server/conf/ca/08bd99c7.0 [/usr/local/esgf-slcs-server/conf/ca/08bd99c7.0 ...], --cacert-chain-filepaths /usr/local/esgf-slcs-server/conf/ca/08bd99c7.0 [/usr/local/esgf-slcs-server/conf/ca/08bd99c7.0 ...]

                        List of PEM-encoded certificate files corresponding to

                        CA trustroot files to be returned in the certificate

                        issuing response. These are concatenated with the new

                        issued certificate. This setting is optional and may

                        be useful where the clients trust roots do not contain

                        the complete chain of trust from the newly issued cert

                        and a root certificate. This option does not apply if

                        the CA for this service is itself a root CA. (default:

                        None)

  -dd, --django-debug   Enable Django debug mode. (default: False)

  -da John Doe,john@example.com [Mary,mary@example.com ...], --django-admin John Doe,john@example.com [Mary,mary@example.com ...]

                        https://docs.djangoproject.com/en/1.10/ref/settings/#a

                        dmins (default: [])

Proxy Settings:

  Settings used when SLCS is operating behind a proxy.

  -up slcs-admin, --url-prefix slcs-admin

                        Should be set when slcs is behind a proxy where all

                        requests are being forwarded from the proxy to slcs.

                        For example, if httpd is being used to proxy all

                        requests for https://my-node.esgf.org/slcs-admin to

                        the slcs application, then this option should be set

                        to 'slcs-admin'. See https://docs.pylonsproject.org/pr

                        ojects/waitress/en/latest/#using-url-prefix-to-

                        influence-script-name-and-path-info. (default: None)

  -xf, --use-x-forwarded-host

                        Enables ALLOWED_HOSTS to match against the

                        X_FORWARDED_HOST HTTP header instead of the HTTP HOST

                        header. See https://docs.djangoproject.com/en/1.9/ref/

                        settings/#use-x-forwarded-host (default: False)

SLCS Database Settings:

  Settings used for connecting to the SLCS database.

  -sdn esgf_slcs_server, --slcs-database-name esgf_slcs_server

                        The SLCS database name. (default: None)

  -sdu db_user, --slcs-database-user db_user

                        The SLCS database user. (default: None)

  -sdh slcsdb.esgf.org, --slcs-database-host slcsdb.esgf.org

                        The SLCS database host. (default: None)

  -sdp 5432, --slcs-database-port 5432

                        The SLCS database port. (default: 5432)

  -sde django.db.backends.postgresql, --slcs-database-engine django.db.backends.postgresql

                        The engine to use for the SLCS database. (default:

                        django.db.backends.postgresql)

User Database Settings:

  Settings used for connecting to the User database.

  -udn esgf_slcs_server, --user-database-name esgf_slcs_server

                        The User database name. (default: None)

  -udu db_user, --user-database-user db_user

                        The User database user. (default: None)

  -udh slcsdb.esgf.org, --user-database-host slcsdb.esgf.org

                        The User database host. (default: None)

  -udt user, --user-database-table user

                        The name of the User table (default: user)

  -uds esgf_security, --user-database-schema esgf_security

                        The name of the schema that contains the User table

                        (default: esgf_security)

  -udp 5432, --user-database-port 5432

                        The User database port. (default: 5432)

  -ude django.db.backends.postgresql, --user-database-engine django.db.backends.postgresql

                        The engine to use for the User database. (default:

                        django.db.backends.postgresql)

```

# Getting a Certificate Using esgf-slcs-client-example

Setup your environment as described in the [wiki](https://github.com/ESGF/esgf-docker/wiki).