ESQL: Signatures for NOT IN et al

This generates signatures for `NOT IN`, `NOT LIKE`, and `NOT RLIKE`
using a small hack on top of the process used to generate the signatures
for `IN`, `LIKE`, and `RLIKE`. This is a very perl-worth hack, replacing
`LIKE` with `NOT LIKE` in the description. But it's useful for our
kibana friends and if we need to make it nicer we can do so later.

Author: nik9000