Add toggle to control invalid character substitution in group names (#52748)

* make add_group return proper name
* ensure central transform/check
* added 'silent' option to avoid spamming current users
  those already using the plugins were used to the transformations, so no need to alert them
* centralized valid var names
* dont display dupes
* comment on regex
* added regex tests
  ini and script will now warn about deprecation
* more complete errormsg

lib/ansible/plugins/inventory/ini.py

@@ -77,6 +77,7 @@ EXAMPLES = '''
 import ast
 import re
 
+from ansible.inventory.group import to_safe_group_name
 from ansible.plugins.inventory import BaseFileInventoryPlugin
 
 from ansible.errors import AnsibleError, AnsibleParserError
@@ -171,6 +172,8 @@ class InventoryModule(BaseFileInventoryPlugin):
             if m:
                 (groupname, state) = m.groups()
 
+                groupname = to_safe_group_name(groupname)
+
                 state = state or 'hosts'
                 if state not in ['hosts', 'children', 'vars']:
                     title = ":".join(m.groups())