tools: import a small tools to compute size of archive policies
tools: import a small tools to compute size of archive policies

Change-Id: I131664319cc9f9c8eda9b5c24e0de04664da3f25

sileht/gnocchi,leandroreox/gnocchi,leandroreox/gnocchi,gnocchixyz/gnocchi,sileht/gnocchi,gnocchixyz/gnocchi