Avoid useless loading of all files by augeas
Avoid useless loading of all files by augeas

If there are files other than bash style config in /etc/sysconfig/pgsql/postgresql, augeas will throw exception
```
Warning: Augeas[override PGDATA in /etc/sysconfig/pgsql/postgresql](provider=augeas): Loading failed for one or more files, see debug for /augeas//error output
```
This commit fixes the issue.
tdevelioglu/puppetlabs-postgresql,npwalker/puppetlabs-postgresql,puppetlabs/puppetlabs-postgresql,fuel-infra/puppetlabs-postgresql,puppetlabs/puppetlabs-postgresql,puppetlabs/puppetlabs-postgresql,DavidS/puppetlabs-postgresql,DavidS/puppetlabs-postgresql,fuel-infra/puppetlabs-postgresql,infoxchange/puppetlabs-postgresql,npwalker/puppetlabs-postgresql,infoxchange/puppetlabs-postgresql,tdevelioglu/puppetlabs-postgresql,hasegeli/puppetlabs-postgresql,buzzdeee/puppetlabs-postgresql,npwalker/puppetlabs-postgresql,DavidS/puppetlabs-postgresql,hasegeli/puppetlabs-postgresql,infoxchange/puppetlabs-postgresql,tdevelioglu/puppetlabs-postgresql,buzzdeee/puppetlabs-postgresql,hasegeli/puppetlabs-postgresql,duritong/puppetlabs-postgresql,fuel-infra/puppetlabs-postgresql,buzzdeee/puppetlabs-postgresql