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##### SUMMARY
Allow to specify a new "format" parameter in "openssl_privatekey". Today the output format is decided by a very simple heuristic which requires further commands to work properly.
I need, for example, to generate a RSA private key but in PKCS8 format. The current heuristic uses OpenSSH format for RSA keys and only uses PKCS8 for Ed25519 and similar. This makes me use a "command" with "openssl" to convert the generated key, which leads to idempotency problems and unnecessary complexity.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
openssl_privatekey

##### ADDITIONAL INFORMATION
<!--- Describe how the feature would be used, why it is needed and what it would solve -->
The current heuristic should be kept unless overwritten by user.

<!--- Paste example playbooks or commands between quotes below -->
```yaml
openssl_privatekey:
  path: /etc/ssl/private/ansible.com.pem
  format: pkcs8
```
The values allowed are `pkcs1`, `raw` and `pkcs8`

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nid = OpenSSL._util.lib.OBJ_txt2nid(to_bytes(name))
    if nid != 0:
        b_name = OpenSSL._util.lib.OBJ_nid2ln(nid)
        name = to_text(OpenSSL._util.ffi.string(b_name))
    if short:
        return _NORMALIZE_NAMES_SHORT.get(name, name)
    else:
        return _NORMALIZE_NAMES.get(name, name)
def _obj2txt(openssl_lib, openssl_ffi, obj):
    
    
    #
    
    
    
    
    #
    buf_len = 80
    buf = openssl_ffi.new("char[]", buf_len)
    
    
    
    res = openssl_lib.OBJ_obj2txt(buf, buf_len, obj, 1)
    if res > buf_len - 1:  
        buf_len = res + 1
        buf = openssl_ffi.new("char[]", buf_len)
        res = openssl_lib.OBJ_obj2txt(buf, buf_len, obj, 1)
    return openssl_ffi.buffer(buf, res)[:].decode()
def cryptography_get_extensions_from_cert(cert):