Atomically return and remove the last (tail) element of the srckey list, and push the element
as the first (head) element of the dstkey list. For example if the source list contains the
elements "a","b","c" and the destination list contains the elements "foo","bar" after an
RPOPLPUSH command the content of the two lists will be "a","b" and "c","foo","bar".
<p>
If the key does not exist or the list is already empty the special value 'nil' is returned. If
the srckey and dstkey are the same the operation is equivalent to removing the last element
from the list and pushing it as first element of the list, so it's a "list rotation" command.
<p>
Time complexity: O(1)
@param srckey
@param dstkey
@return Bulk reply
Atomically return and remove the last (tail) element of the srckey list, and push the element as the first (head) element of the dstkey list. For example if the source list contains the elements "a","b","c" and the destination list contains the elements "foo","bar" after an RPOPLPUSH command the content of the two lists will be "a","b" and "c","foo","bar". <p> If the key does not exist or the list is already empty the special value 'nil' is returned. If the srckey and dstkey are the same the operation is equivalent to removing the last element from the list and pushing it as first element of the list, so it's a "list rotation" command. <p> Time complexity: O(1) @param srckey @param dstkey @return Bulk reply