Method lower_bound

fdbclient/VersionedMap.cpp:55–55

	result begin() const { return result(s.atLatest().begin()); }
	result end() const { return result(s.atLatest().end()); }
	result lower_bound(K const& k) const { return result(s.atLatest().lower_bound(k)); }
	result upper_bound(K const& k) const { return result(s.atLatest().upper_bound(k)); }
	void erase(K const& k) { s.erase(k); }
};