hydiomatic.rules: Add comments above the rules

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
hydiomatic.rules: (+ x (+ ...)) => (+ x ...)

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
hydiomatic.rules: Remove unneeded imports

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
hydiomatic: Quasiquote > ad-hoc quoting

Many thanks to Nicolas Dandrimont <nicolas.dandrimont@crans.org> for the
idea and help.

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