cli: generate-db-secrets

* Changes ``--generate-default-secrets`` to ``--generate-db-secrets``
  when invoking or mentioning ``reana-cluster init``.
 (closes #209)

Signed-off-by: Tibor Šimko <tibor.simko@cern.ch>

docs/developerguide.rst

@@ -544,7 +544,7 @@ And now you can start the cluster as ``reana-cluster`` docs say:
 
 .. code:: console
 
-    $ reana-cluster init --traefik
+    $ reana-cluster init --traefik --generate-db-secrets
     REANA cluster is initialised
 
 Check that all components are created:

docs/gettingstarted.rst

@@ -41,7 +41,7 @@ Are you looking at installing and deploying REANA cluster locally on your laptop
 
    .. code-block:: console
 
-      $ reana-cluster init --traefik --generate-default-secrets
+      $ reana-cluster init --traefik --generate-db-secrets
 
   .. note::
 

docs/userguide.rst

@@ -176,7 +176,7 @@ Initialising a REANA cluster is just a matter of running ``init`` command:
 
 .. code-block:: console
 
-   $ reana-cluster init --traefik --generate-default-secrets
+   $ reana-cluster init --traefik --generate-db-secrets
    REANA cluster is initialised.
 
 If you have created a custom configuration, you can use the ``-f`` command-line
@@ -185,7 +185,8 @@ option and specify your own file. In the same way you can set URL for REANA clus
 
 .. code-block:: console
 
-  $ reana-cluster -f reana-cluster-custom.yaml --url reana.cern.ch init --traefik
+  $ reana-cluster -f reana-cluster-custom.yaml --url reana.cern.ch init \\
+                  --traefik --generate-db-secrets
 
 
 Verify REANA components

reana_cluster/cli/cluster.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 #
 # This file is part of REANA.
-# Copyright (C) 2017, 2018 CERN.
+# Copyright (C) 2017, 2018, 2019 CERN.
 #
 # REANA is free software; you can redistribute it and/or modify it
 # under the terms of the MIT License; see LICENSE file for more details.
@@ -155,15 +155,15 @@ def restart(ctx, remove_persistent_storage):
     '--traefik', is_flag=True,
     help='Install and initialize Traefik')
 @click.option(
-    '--generate-default-secrets', is_flag=True,
-    help='Create all needed secrets with default values. Do not use this in'
-         'production deployments')
+    '--generate-db-secrets', is_flag=True,
+    help='Create all necessary database secrets. Do not use this in'
+         'production deployments.')
 @click.pass_context
-def init(ctx, skip_initialization, output, traefik, generate_default_secrets):
+def init(ctx, skip_initialization, output, traefik, generate_db_secrets):
     """Initialize REANA cluster."""
     try:
         reana_db_secret_exists = is_reana_db_secret_created()
-        if not reana_db_secret_exists and generate_default_secrets:
+        if not reana_db_secret_exists and generate_db_secrets:
             create_reana_db_secret()
         elif not reana_db_secret_exists:
             click.echo(click.style(