add exception class and line number

[vetinari]

to exceptions for checks and alerts. This way we get a better message
for the users, e.g. a

KeyError line 4: 'foo'

instead of just

'foo'

[codecov]

Codecov Report

Merging #310 into master will increase coverage by <.01%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##           master     #310      +/-   ##
==========================================
+ Coverage   75.61%   75.62%   +<.01%     
==========================================
  Files          78       78              
  Lines        5447     5452       +5     
==========================================
+ Hits         4119     4123       +4     
- Misses       1328     1329       +1

Impacted Files	Coverage Δ
zmon_worker_monitor/zmon_worker/tasks/main.py	76.16% <83.33%> (+0.02%)	⬆️

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[vetinari]

👍

[aermakov-zalando]

🎉

[aermakov-zalando]

Is it possible to add a note about the exception source as well, e.g. KeyError check line 20?

[mohabusama]

@aermakov-zalando Full stacktrace in the works 😉

[vetinari]

👍

[mohabusama]

👍