Merge pull request #320 from CrashenX/missing_exception_import_in_tests

added missing import for qonos exceptions
Fix localization error in exception.py

Fix issue:-
qonos/common/exception.py:31:48: H701  Empty localization string

Also, localizes strings for other exceptions as well.
Merge pull request #319 from komawar/fix-localization-in-exception

Fix localization error in exception.py
Refactor timeout backoff logic

When an error occurs processing a job, the worker sets the timeout based on the
backoff logic and abandons the job. The job can then later be picked back up by
an available worker when the timeout expires. Currently the backoff logic
supports exponential backoff with a default increment value of 3 hours. I
propose a fibonacci backoff with more reasonable values.

e.g.

5s
10s
15s
25s
40s
1.08m
1.75m
2.83m
4.58m
7.42m
12.00m
19.42m
31.42m
50.83m
1.37h
2.22h
3.59h
5.81h
9.40h

RM7469