This patch adds a method get_ranges() to replication-strategy.
It returns the list of token ranges held by the given endpoint.
It will be used by the replication code, which needs to know
in particular which token ranges are held by *this* node.
This function is the analogue of Origin's getAddressRanges().get(endpoint).
As in Origin, also here the implementation is not meant to be efficient,
and will not be used in the fast path.
Signed-off-by: Nadav Har'El <nyh@cloudius-systems.com>
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