Add resources.GetRemote

Add resources.GetRemote

In Hugo 0.89 we added remote support to `resources.Get`.

In hindsight that was not a great idea, as a poll from many Hugo users showed. See Issue #9285 for more details.

After this commit `resources.Get` only supports local resource lookups. If you want to support both, you need to use a construct similar to:

Also improve some option case handling.

```
{{ resource := "" }}
{{ if (urls.Parse $url).IsAbs }}
{{ $resource = resources.GetRemote $url }}
{{ else }}
{{ $resource = resources.Get $url }}
{{ end }}
```

Fixes #9285
Fixes #9296