logging: remove object-specific loggers

Remove all object-specific loggers, with the exception of `Plugin.log`,
which is now deprecated. Replace affected logger calls with module-level
logger calls.

Deprecate object-specific loggers in `ipa_log_manager.get_logger`.

Reviewed-By: Martin Basti <mbasti@redhat.com>

ipaserver/plugins/passwd.py

@@ -17,6 +17,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
+
 import six
 
 from ipalib import api, errors, krb_utils
@@ -54,6 +56,8 @@ EXAMPLES:
    ipa passwd tuser1
 """)
 
+logger = logging.getLogger(__name__)
+
 register = Registry()
 
 # We only need to prompt for the current password when changing a password
@@ -134,7 +138,8 @@ class passwd(Command):
         if principal == getattr(context, 'principal') and \
             current_password == MAGIC_VALUE:
             # No cheating
-            self.log.warning('User attempted to change password using magic value')
+            logger.warning('User attempted to change password using magic '
+                           'value')
             raise errors.ACIError(info=_('Invalid credentials'))
 
         if current_password == MAGIC_VALUE: