saltstack/salt — pull request #10013 by bretep (2014-01-29 06:19:40+00:00)
Title: Add ability to subfilter in sls files

This will recurse through the sls when matching the minion.

It will only recurse on the special key: subfilter

Why subfilters? There a few benefits. Notice in the example below
the top most filter is environment specific. All the sub filters can
be copied, as is, beneath any filter. No more writing '*dev*web*front'
anymore.

For further documentation on why this was added:
Please see issue saltstack/salt#9979

Here is an example sls:

```yaml
dev:
'*dev*':
- sqlite
- subfilter:
'*webserver*':
- nginx
prod:
'*prod*':
- stunnle
- subfilter:
'*webserver*':
- newrelic-agent
- subfilter:
'*front':
- haproxy
'*back':
- nginx
- statsd
```