help text for juju add-credential needs improving

[Peter Matulis]

e.g.:

Usage: juju add-credential [options] <cloud name>

Summary:
Adds or replaces credentials for a cloud.

Options:

-f (= "")
    Path to YAML credentials file
--replace (= false)
    Overwrite existing credential information

Details:
The user is prompted to add credentials interactively if a YAML-formatted credentials file is not specified. Here is a sample credentials file:

credentials:
   aws:
        <credential name>:
            auth-type: access-key
            access-key: <key>
            secret-key: <key>
   azure:
        <credential name>:
            auth-type: userpass
            application-id: <uuid1>
            application-password: <password>
            subscription-id: <uuid2>
            tenant-id: <uuid3>

A "credential name" is arbitrary and is used solely to represent a set of credentials, of which there may be multiple per cloud.
The `--replace` option is required if credential information for the named cloud already exists. All such information will be overwritten.
This command does not set default regions nor default credentials. Note that if only one credential name exists, it will become the effective default credential.
For credentials which are already in use by tools other than Juju, `juju autoload-credentials` may be used.
When Juju needs credentials for a cloud, i) if there are multiple available; ii) there's no set default; iii) and one is not specified ('--credential'), an error will be emitted.

Examples:

    juju add-credential google
    juju add-credential aws -f ~/credentials.yaml

See also: list-credentials
          remove-credential
          set-default-credential
          autoload-credentials

[Reed O'Brien (reedobrien)]

Output:

Usage: juju add-credential [options] <cloud name>

Summary:
Adds or replaces credentials for a cloud.

Options:
-f (= "")
    The YAML file containing credentials to add
--replace (= false)
    Overwrite existing credential information

Details:
The user is prompted to add credentials interactively if a YAML-formatted
credentials file is not specified. Here is a sample credentials file:

credentials:
  aws:
    <credential name>:
      auth-type: access-key
      access-key: <key>
      secret-key: <key>
  azure:
    <credential name>:
      auth-type: userpass
      application-id: <uuid1>
      application-password: <password>
      subscription-id: <uuid2>
      tenant-id: <uuid3>

A "credential name" is arbitrary and is used solely to represent a set of
credentials, of which there may be multiple per cloud.
The `--replace` option is required if credential information for the named
cloud already exists. All such information will be overwritten.
This command does not set default regions nor default credentials. Note
that if only one credential name exists, it will become the effective
default credential.
For credentials which are already in use by tools other than Juju, `juju
autoload-credentials` may be used.
When Juju needs credentials for a cloud, i) if there are multiple
available; ii) there's no set default; iii) and one is not specified ('--
credential'), an error will be emitted.

Examples:
    juju add-credential google
    juju add-credential aws -f ~/credentials.yaml

See also:
    list-credentials
    remove-credential
    set-default-credential
    autoload-credentials