rules/equalityᵒ: Add a (not (is x y)) => (is-not x y) rule

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
rules/equalityᵒ: Add a (not (= x y)) => (!= x y) rule

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
rules/equalityᵒ: Add a (not (in a b)) => (not-in a b) rule

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
rules/equalityᵒ: Improve the (not (...)) rules

The recently added (not (is ...)), (not (= ...)) and (not (in ...))
rules only handled two arguments, while the syntax allows for more. We
should allow for more too.

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
bin/hydiomatic: Use != instead of (not (= ...))

Thanks hydiomatic!

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>