Previously translated messages are included in log messages
and it was determined what language is chosen by users.
It makes difficult for operators to understand log messgaes.
This commit tries to use English messages for all log messages.
The following policies are applied based on the past discussions
in the bug 1406333 and related reviews.
- English messages are used for log messages.
- log messages include exception messages if possible
to help operators identify what happens.
- Use ID rather than name for log messages
as ID is much more unique compared to name.
- LOG.debug() in success code path are deleted.
We don't log success messages in most places and API calls to
back-end services can be logged from python bindings.
Change-Id: Ie554463908327435d886d0d0f1671fd327c0cd00
Closes-Bug: #1406333