PSMDB-810 improve logging#695

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igorsol wants to merge 3 commits intov4.2from

Commits on Feb 12, 2021

PSMDB-810 explicitly close destination file to avoid error swallowing
igorsol
committed
PSMDB-810 output more information in case of exception while copying
igorsol
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Commits on Feb 16, 2021

PSMDB-810 log more info during hot backup
igorsol
committed