Fix: Fixed warnings reported by PyLint.

(Redmine issue: #3443)

lib/vial/app.py

@@ -13,7 +13,6 @@ classes that form the new base of *Vial* application.
 
 import sys
 import traceback
-import os
 import datetime
 import weakref
 import jinja2

lib/vial/intl.py

@@ -10,17 +10,11 @@ This module contains usefull internationalization utilities for *Vial* applicati
 """
 
 
-import os
-
-import click
 import flask
-from flask.cli import AppGroup
 import flask_babel
 import flask_login
 from babel import Locale
 
-import vial.const
-
 
 BABEL = flask_babel.Babel()
 @BABEL.localeselector