Adds redis_data_info module (#3227)

* Added redis_data_info module

Added:
  - redis_data_info module and suggested 'exists' return flag.
  - module_utils for redis with a base class that handles database connections.
  - inhereited unit tests and added some new ones for the exit flag

* Docfix and sanity

* typo

* Suggested doc changes and ssl option

* TLS and validate_certs fix

* Set support_check_mode for info plugin

* Docfix and import errors

* Redis versioning Fix

* version bump and append fixes

plugins/doc_fragments/redis.py

@@ -0,0 +1,57 @@
+# -*- coding: utf-8 -*-
+
+# Copyright: (c) 2021, Andreas Botzner <andreas at botzner dot com>
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import (absolute_import, division, print_function)
+__metaclass__ = type
+
+
+class ModuleDocFragment(object):
+    # Common parameters for Redis modules
+    DOCUMENTATION = r'''
+options:
+  login_host:
+    description:
+      - Specify the target host running the database.
+    default: localhost
+    type: str
+  login_port:
+    description:
+      - Specify the port to connect to.
+    default: 6379
+    type: int
+  login_user:
+    description:
+      - Specify the user to authenticate with.
+      - Requires L(redis,https://pypi.org/project/redis) >= 3.4.0.
+    type: str
+  login_password:
+    description:
+      - Specify the password to authenticate with.
+      - Usually not used when target is localhost.
+    type: str
+  tls:
+    description:
+      - Specify whether or not to use TLS for the connection.
+    type: bool
+    default: true
+  validate_certs:
+    description:
+      - Specify whether or not to validate TLS certificates.
+      - This should only be turned off for personally controlled sites or with
+        C(localhost) as target.
+    type: bool
+    default: true
+  ca_certs:
+    description:
+      - Path to root certificates file. If not set and I(tls) is
+        set to C(true), certifi ca-certificates will be used.
+    type: str
+requirements: [ "redis", "certifi" ]
+
+notes:
+  - Requires the C(redis) Python package on the remote host. You can
+    install it with pip (C(pip install redis)) or with a package manager.
+    Information on the library can be found at U(https://github.com/andymccurdy/redis-py).
+'''