##### 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
```

RETURN = r'''
dest:
    description: Destination file/path
    returned: success
    type: str
    sample: /path/to/file.txt
src:
    description: Source file used for the copy on the target machine
    returned: changed
    type: str
    sample: /home/httpd/.ansible/tmp/ansible-tmp-1423796390.97-147729857856000/source
md5sum:
    description: MD5 checksum of the file after running copy
    returned: when supported
    type: str
    sample: 2a5aeecc61dc98c4d780b14b330e3282
checksum:
    description: SHA1 checksum of the file after running copy
    returned: success
    type: str
    sample: 6e642bb8dd5c2e027bf21dd923337cbb4214f827
backup_file:
    description: Name of backup file created
    returned: changed and if backup=yes
    type: str
    sample: /path/to/file.txt.2015-02-12@22:09~
gid:
    description: Group id of the file, after execution
    returned: success
    type: int