##### SUMMARY
If a module sets `add_file_common_args=True` when calling `AnsibleModule`, all elements from [FILE_COMMON_ARGUMENTS](https://github.com/ansible/ansible/blob/e9d29b1fe4285d90d7a4506b80260a9e24c3bcea/lib/ansible/module_utils/basic.py#L229-L257) are included in the argument spec. The [files document fragment](https://github.com/ansible/ansible/blob/e9d29b1fe4285d90d7a4506b80260a9e24c3bcea/lib/ansible/plugins/doc_fragments/files.py#L15-L80) only documents a subset of them, though. Missing are:
 - src
 - follow
 - force
 - content
 - backup
 - remote_src
 - regexp
 - delimiter
 - directory_mode

Most module authors using `add_file_common_args=True` are probably not aware that their modules have these options as well.

I don't think these extra options should be added by default if `add_file_common_args=True` is specified.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
lib/ansible/module_utils/basic.py

##### ANSIBLE VERSION
```
devel
```

"""remove action plugin only keys"""
    return dict((k, v) for k, v in module_args.items() if k not in ('content', 'decrypt'))
def _walk_dirs(topdir, base_path=None, local_follow=False, trailing_slash_detector=None):
    """
    Walk a filesystem tree returning enough information to copy the files
    :arg topdir: The directory that the filesystem tree is rooted at
    :kwarg base_path: The initial directory structure to strip off of the
        files for the destination directory.  If this is None (the default),
        the base_path is set to ``top_dir``.
    :kwarg local_follow: Whether to follow symlinks on the source.  When set
        to False, no symlinks are dereferenced.  When set to True (the
        default), the code will dereference most symlinks.  However, symlinks
        can still be present if needed to break a circular link.
    :kwarg trailing_slash_detector: Function to determine if a path has
        a trailing directory separator. Only needed when dealing with paths on
        a remote machine (in which case, pass in a function that is aware of the
        directory separator conventions on the remote machine).
    :returns: dictionary of tuples.  All of the path elements in the structure are text strings.
            This separates all the files, directories, and symlinks along with
            important information about each::
                { 'files': [('/absolute/path/to/copy/from', 'relative/path/to/copy/to'), ...],
                  'directories': [('/absolute/path/to/copy/from', 'relative/path/to/copy/to'), ...],
                  'symlinks': [('/symlink/target/path', 'relative/path/to/copy/to'), ...],
                }
        The ``symlinks`` field is only populated if ``local_follow`` is set to False
        *or* a circular symlink cannot be dereferenced.
    """
    
    r_files = {'files': [], 'directories': [], 'symlinks': []}
    def _recurse(topdir, rel_offset, parent_dirs, rel_base=u''):