Refactor session db logging and key generation for sessions/otks While I was working on the redis sessiondb stuff, I noticed that log_wanrning, get_logger ... was duplicated. Also there was code to generate a unique key for otks that was duplicated. Changes: creating new sessions_common.py and SessionsCommon class to provide methods: log_warning, log_info, log_debug, get_logger, getUniqueKey getUniqueKey method is closer to the method used to make session keys in client.py. sessions_common.py now report when random_.py chooses a weak random number generator. Removed same from rest.py. get_logger reconciles all logging under roundup.hyperdb.backends.<name of BasicDatabase class> some backends used to log to root logger. have BasicDatabase in other sessions_*.py modules inherit from SessionCommon. change logging to use log_* methods. In addition: remove unused imports reported by flake8 and other formatting changes modify actions.py, rest.py, templating.py to use getUniqueKey method. add tests for new methods test_redis_session.py swap out ModuleNotFoundError for ImportError to prevent crash in python2 when redis is not present. allow injection of username:password or just password into redis connection URL. set pytest_redis_pw envirnment variable to password or user:password when running test.

#  - "path/to/folder"  # ignore folders and all its contents
#  - "test_*.rb"       # wildcards accepted
#  - "**/*.py"         # glob accepted
#  - "[a-z]+/test_.*"  # regexp accepted

# ignore files that are build utils and not executed
# code, or are deprecated.
ignore:
   - "roundup/cgi/TAL/talgettext.py" # utility command
   - "roundup/cgi/TAL/DummyEngine.py" # test harness
   - "roundup/cgi/apache.py"  # mod_python is deprecated
   - "roundup/install_util.py" # another build utlity
   - "roundup/dist"           # more build utils
   - "roundup/test"           # code used for testing