Doc fragments to plugins (#50172)

* promote doc_fragments into actual plugins

  change tests hardcoded path to doc fragments
  avoid sanity in fragments
  avoid improper testing of doc_fragments
  also change runner paths
 fix botmeta
 updated comment for fragments
 updated docs

lib/ansible/plugins/doc_fragments/default_callback.py

@@ -0,0 +1,51 @@
+# (c) 2017 Ansible Project
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+
+class ModuleDocFragment(object):
+
+    DOCUMENTATION = """
+    options:
+      display_skipped_hosts:
+        name: Show skipped hosts
+        description: "Toggle to control displaying skipped task/host results in a task"
+        default: True
+        env:
+          - name: DISPLAY_SKIPPED_HOSTS
+        ini:
+          - key: display_skipped_hosts
+            section: defaults
+        type: boolean
+      display_ok_hosts:
+        name: Show 'ok' hosts
+        description: "Toggle to control displaying 'ok' task/host results in a task"
+        default: True
+        env:
+          - name: ANSIBLE_DISPLAY_OK_HOSTS
+        ini:
+          - key: display_ok_hosts
+            section: defaults
+        type: boolean
+        version_added: '2.7'
+      display_failed_stderr:
+        name: Use STDERR for failed and unreachable tasks
+        description: "Toggle to control whether failed and unreachable tasks are displayed to STDERR (vs. STDOUT)"
+        default: False
+        env:
+          - name: ANSIBLE_DISPLAY_FAILED_STDERR
+        ini:
+          - key: display_failed_stderr
+            section: defaults
+        type: boolean
+        version_added: '2.7'
+      show_custom_stats:
+        name: Show custom stats
+        description: 'This adds the custom stats set via the set_stats plugin to the play recap'
+        default: False
+        env:
+          - name: ANSIBLE_SHOW_CUSTOM_STATS
+        ini:
+          - key: show_custom_stats
+            section: defaults
+        type: bool
+"""