Adding simple In support

[FreCap]

This works for field IN (list...)

The support to subqueries in the IN clause is yet to come.

[chloe-zh]

Hi @FreCap thanks for your contributions! Left some comments, the rest looks good to me.

I wonder shall we also add the IN (as well as BETWEEN ... AND ...) in PPL where command (or condition clause in search command), that would be helpful for PPL as well @penghuo