Reordered checking for --update flag and checking for no other args

[shreyb]

Reordered pre-FerryCLI steps so that they are:

1. Parse our auth args
2. Set up the credential
3. Check for --update flag
4. Check to see if we have other args and DON'T have the --update flag set

Tests are in the comments below.

[shreyb]

Checks:

$ bin/ferry-cli --update
Fetching latest swagger file...
Successfully stored latest swagger file.

No more arguments provided. Exiting.

And now with post-actions:

$ bin/ferry-cli --update -e getUserInfo --username me
Fetching latest swagger file...
Successfully stored latest swagger file.

{
    "ferry_status": "success",
    "ferry_error": [],
    "ferry_output": {
        "banned": false,
        "expirationdate": "2038-01-01T00:00:00Z",
VARIOUS REDACTED INFO
    },
    "request_url": "REDACTED"
}

And now with no --update, and no args either:

$ bin/ferry-cli 
Configuration file already exists at /home/sbhat/.config/ferry_cli/config.ini. Are you sure you want to overwrite it (Y/[n])?  n
A configuration file is required to run the Ferry CLI. Please run "ferry-cli" to generate one interactively if one does not already exist.
usage: ferry-cli [-h] [-a AUTH_METHOD] [--token-path TOKEN_PATH | --cert-path CERT_PATH] [--ca-path CA_PATH] [--dryrun | -d | -q] [-u] [--support_email] [--version]
                 [--output OUTPUT] [--filter FILTER] [-le] [-lw] [-ep ENDPOINT_PARAMS] [-wp WORKFLOW_PARAMS] [-e ENDPOINT] [-w WORKFLOW] [--show-config-file]

CLI for Ferry API endpoints

optional arguments:
  -h, --help            show this help message and exit
  -a AUTH_METHOD, --auth-method AUTH_METHOD
                        Auth method for FERRY request
  --token-path TOKEN_PATH
                        Path to bearer token
  --cert-path CERT_PATH
                        Path to cert
  --ca-path CA_PATH     Certificate authority path
  --dryrun              Populate the API call(s) but don't actually run them
  -d, --debug           Turn on debugging
  -q, --quiet           Hide output
  -u, --update          Get latest swagger file
  --support_email       Get Ferry CLI support emails
  --version             Get Ferry CLI version
  --output OUTPUT       (string) Specifies the path to a file where the output will be stored in JSON format. If a file already exists in the specified path, it will be
                        overritten.
  --filter FILTER       (string) Use to filter results on -le and -lw flags
  -le, --list_endpoints, --list-endpoints
                        List all available endpoints
  -lw, --list_workflows, --list-workflows
                        List all supported custom workflows
  -ep ENDPOINT_PARAMS, --endpoint_params ENDPOINT_PARAMS, --endpoint-params ENDPOINT_PARAMS
                        List parameters for the selected endpoint
  -wp WORKFLOW_PARAMS, --workflow_params WORKFLOW_PARAMS, --workflow-params WORKFLOW_PARAMS
                        List parameters for the supported workflow
  -e ENDPOINT, --endpoint ENDPOINT
                        API endpoint and parameters
  -w WORKFLOW, --workflow WORKFLOW
                        Execute supported workflows
  --show-config-file    Locate and print configuration file, if it exists, then exit.
Exiting without writing configuration file.

[shreyb]

Cleaned up the code a little bit:

I added two new optional arguments to the FerryCLI class instantiation: print_help and authorizer

print_help will bypass most of the class instantiation and simply print help from the FerryCLI.get_arg_parser(), then return

authorizer passes in the Auth subclass that will be used to authorize the FerryCLI queries

[cathulhu]

quite sensible changes.