Refactor dimensiondata_network module (#21043)

* Refactor dimensiondata_network to use shared base class for common functionality.

* Experiment: remove the assignments in the "except ImportError:" block that keep PyCharm happy. If this fixes the build, then I reckon there's a bug in the validate-modules script (https://github.com/ansible/ansible/blob/devel/test/sanity/validate-modules/validate-modules#L322).

* Remove unused imports.

* Changes based on feedback from @gundalow for ansible/ansible#21043.

- Use no_log=True for mcp_password parameter.
- Collapse module parameter definitions.

* Use shared definitions and doc fragments for common module arguments (ansible/ansible#21043).

* Make default network plan "ESSENTIALS", rather than "ADVANCED" (this is consistent with our other tooling).
Tidy up module parameter documentation.

* Simplify dimensiondata module documentation fragments (didn't know you could include multiple fragments).

* Change 'verify_ssl_cert' module parameter to 'validate_certs'.

lib/ansible/utils/module_docs_fragments/dimensiondata.py

@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (c) 2016 Dimension Data
+#
+# This module is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This software is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this software.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Authors:
+#   - Adam Friedman  <tintoy@tintoy.io>
+
+
+class ModuleDocFragment(object):
+
+    # Dimension Data doc fragment
+    DOCUMENTATION = '''
+
+options:
+  region:
+    description:
+      - The target region.
+    choices:
+      - Regions are defined in Apache libcloud project [libcloud/common/dimensiondata.py]
+      - They are also listed in U(https://libcloud.readthedocs.io/en/latest/compute/drivers/dimensiondata.html)
+      - Note that the default value "na" stands for "North America".
+      - The module prepends 'dd-' to the region choice.
+    default: na
+  mcp_user:
+    description:
+      - The username used to authenticate to the CloudControl API.
+      - If not specified, will fall back to C(MCP_USER) from environment variable or C(~/.dimensiondata).
+    required: false
+  mcp_password:
+    description:
+      - The password used to authenticate to the CloudControl API.
+      - If not specified, will fall back to C(MCP_PASSWORD) from environment variable or C(~/.dimensiondata).
+      - Required if I(mcp_user) is specified.
+    required: false
+  location:
+    description:
+      - The target datacenter.
+    required: true
+  validate_certs:
+    description:
+      - If C(false), SSL certificates will not be validated.
+      - This should only be used on private instances of the CloudControl API that use self-signed certificates.
+    required: false
+    default: true
+    '''