Removed the progress_handler from the engine
Avoided spurious errors for non-initialized sites
Autoremoving the logging handler
The same error and traceback are reported even with OQ_NO_DISTRIBUTE=1
Fixed oqtask
Merge branch 'master' of github.com:gem/oq-engine into saner-progress-handler
Merge pull request #1370 from gem/saner-progress-handler

Removed the progress handler from the engine