Fix for [Errno 49] Can't assign requested address

Fix to issue #119

…nto develop

Dmm test cleanup

…e develop branch... but trendlogs property was not referenced as self.trendlogs.

…019 and 0 means (for now) still working on it

…variable trendlogs is part of the return of the function and must stay local to the function. But the way trendLogs are implemented needs some thinking as it is complicated to retrieve... we must access the object in the dict....the call read_log_buffer().... the access to its history property. There must be a better way. Committing for now

… need to handle the exception and return something...sot an empty string that equals None... Now BAC0 will show Not Implemented in the description if it doesn't exist in the controller

… of communication errors

…ing of errors related to already used socket or ip addresses