`ON CONFLICT (column) IGNORE` for batch insert(Postgres)

[NPCRUS]

Capability to do ON CONFLICT IGNORE for batch inserts is missing with PostgreslDialect

desired behaviour:

TableA.insert.values(
  TableA(0, "a"), TableA(0, "b")
).onConflictIgnore(_.name)

[aboisvert]

If it gives you any motivation, I'd be interested in this as well :)