Removes the `uniq` constraint on `after` and `before` so that we can
merge multiple definitions for the same DAG entry:
{
dag = mkMerge [
{
foo = lib.hm.dag.entryBefore [ "bar" ] {
# definition 1
};
}
{
foo = lib.hm.dag.entryBefore [ "qux" ] {
# definition 2
};
}
{
foo = {
# definition 3
};
}
];
}
In this example `foo` will come before `bar` and `qux`.