[fix] #278: changing regex for PubSec authfile authentication

• use Duniterpy's regexp for authfile checking
• document the function auth_by_auth_file()

• Close #278 (closed) .

silkaj/auth.py

@@ -16,13 +16,15 @@ along with Silkaj. If not, see <https://www.gnu.org/licenses/>.
 """
 
 import re
-from silkaj.tools import message_exit
 from click import command, option, pass_context, confirm
 from getpass import getpass
 from pathlib import Path
+
 from duniterpy.key import SigningKey
 from duniterpy.key.scrypt_params import ScryptParams
 
+from silkaj.tools import message_exit
+
 
 @pass_context
 def auth_method(ctx):