Log unhandled exceptions during task execution
Log unhandled exceptions during task execution

Partially implements blueprint improve-engine-logging
Change-Id: I65196d3216d1c35b7f1d53c1c1e0f0421ecc7c68

DavidPurcell/murano_temp,openstack/murano,olivierlemasle/murano,ativelkov/murano-api,NeCTAR-RC/murano,satish-avninetworks/murano,ativelkov/murano-api,DavidPurcell/murano_temp,olivierlemasle/murano,sajuptpm/murano,telefonicaid/murano,telefonicaid/murano,NeCTAR-RC/murano,sajuptpm/murano,openstack/murano,NeCTAR-RC/murano,satish-avninetworks/murano,sergmelikyan/murano,chenyujie/hybrid-murano,satish-avninetworks/murano,NeCTAR-RC/murano,sergmelikyan/murano,DavidPurcell/murano_temp,DavidPurcell/murano_temp,chenyujie/hybrid-murano,satish-avninetworks/murano,olivierlemasle/murano,olivierlemasle/murano