Fix intersect issue

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Slightly optimize implicit delete case, add tests

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Optimize set.rank

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Add test for unique option revert in set.set

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Optimize set._remove

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Optimize slice toArray case

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Add set.gut, set.gutSlice and tests

Not terribly fond of the naming here, but it works. Similar to redis'
ZREMRANGEBYSCORE and ZREMRANGEBYRANK, respectively.

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
Add TTL example

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>
[0.1.8] version bump

Signed-off-by: Eli Skeggs <eskeggs@globesherpa.com>