Implement logging handler for cv_client / cv_api #124

Configure a dedicated logging.handler to log cv_client and cv_api
fucntions:

```
arista.cvp.cv_client: DEBUG - func: get_inventory (L:105) -
get_inventory: called
arista.cvp.cv_client: DEBUG - func: get_inventory (L:106) - 2019
Inventory API Call
```

ansible_collections/arista/cvp/plugins/module_utils/cv_api2019.py

@@ -895,7 +895,7 @@ def get_container_by_name(self, name):
                 container (dict): Container info in dictionary format or None
         '''
         self.log.debug('Get info for container %s' % name)
-        logging.debug(
+        self.log.debug(
             '* cv_api2019 - get_container_by_name - container name is: %s', str(name))
         containers = self.clnt.get('/provisioning/searchTopology.do?queryParam=%s'
                                    '&startIndex=0&endIndex=0' % qplus(name))

ansible_collections/arista/cvp/plugins/module_utils/cv_client.py

@@ -89,6 +89,7 @@
 import inspect
 import traceback
 from logging.handlers import SysLogHandler
+import ansible_collections.arista.cvp.plugins.module_utils.logger
 from itertools import cycle
 from ansible_collections.arista.cvp.plugins.module_utils.cv_client_errors import CvpApiError, CvpLoginError, CvpRequestError, CvpSessionLogOutError
 REQUESTS_IMP_ERR = None
@@ -144,8 +145,8 @@ def __init__(self, logger='cv_apiClient', syslog=False, filename=None,
         self.headers = {'Accept': 'application/json',
                         'Content-Type': 'application/json'}
 
-        self.log = logging.getLogger(logger)
-        self.set_log_level(log_level)
+        self.log = logging.getLogger('arista.cvp.cv_client')
+        self.log.info('Start cv_client API execution')
         if syslog:
             # Enables sending logging messages to the local syslog server.
             self.log.addHandler(SysLogHandler())
@@ -278,6 +279,7 @@ def connect(self, nodes, username, password, connect_timeout=10,
         self._create_session(all_nodes=True)
         # Verify that we can connect to at least one node
         if not self.session:
+            self.log.error(' error connecting cvp: %s', str(self.error_msg))
             raise CvpLoginError(self.error_msg)
         else:
             # Instantiate the CvpApi class