Create Link Command improvement when the destination field is a @RID

When the source field is a String that refers to @RID (so the destination field is a @RID) the query to get the destination record can be improved to search by id.

The following command:

CREATE LINK comments TYPE LINKSET FROM comment.postId TO post.@rid INVERSE

has been tested with 3400 posts. Each post has 50 comments for a total of 170K comments.

The previous version takes about 30 minutes to complete. With the new version it executes in less than a minute.