[core]: Adds support for on_error to abort further event handlers on exceptions

[prologic]

Closes #128

[codecov-io]

Codecov Report

:exclamation: No coverage uploaded for pull request base (master@1b69122). Click here to learn what that means. The diff coverage is 61.11%.

@@           Coverage Diff            @@
##             master    #220   +/-   ##
========================================
  Coverage          ?   77.1%           
========================================
  Files             ?      80           
  Lines             ?    6700           
  Branches          ?       0           
========================================
  Hits              ?    5166           
  Misses            ?    1534           
  Partials          ?       0

Impacted Files	Coverage Δ
circuits/core/handlers.py	100% <100%> (ø)
circuits/core/events.py	96.9% <100%> (ø)
circuits/core/manager.py	92.62% <56.25%> (ø)

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[spaceone]

@prologic Why do you close this and remove the branch?

[prologic]

Ahh I was doing some Github cleanup! Sorry, do you want to take over the branch/PR?

[spaceone]

I can't promise to work on this currently, but I still would need it. I restore the branch to not remove the current working state.