Correct totalConnections metric

Correct totalConnections metric

In previous implementation performed healthcheck on container
was counted as client connection, because metric was notified
for every TCP channel opened. This was making this metric less useful
(to avoid saying "useless" ;) ).

- refactored NettyTcpServer trying to extract functions with logic
not so strictly related to HV-VES behavior. This also resolves
discussions in https://gerrit.onap.org/r/#/c/76274/
- some renames and methods splitting was made in attempt to make code
more readable
- hv-ves should not count connections from either "127.0.0.1" or
"localhost" to his `totalConnections` metric
- removed redundant logging by adding new methods to Logger

Change-Id: I5f10dac8dac82eafd3b0de92a7ec43f2c23b8c16
Issue-ID: DCAEGEN2-1119
Signed-off-by: Filip Krzywka <filip.krzywka@nokia.com>