Turned methods of Configuration into private methods.
Snapshots without a timestamp now have a .0 extension.

If a synchronizing process is interrupted and resumed some time later,
it is not relevant for it to have a timestamp before it is completed.
Until the timestamp property is assigned a datetime value, it is None
and the path extension is .0 in order to appear first in sorted
directory listings.
Renamed method execute() to sync_to(dest) in rsyncWrapper.
Stream handler is now added to the root logger in main().

The Controller instance did this, but this would interfere with unit
testing.
Edited file header comments for uniformity and conformity.