Support Directory Environments in config

[bmcclure]

Directory Environments are overtaking Config File Environments (the latter being deprecated now). I think all that is really necessary to support the former is adding a line to the [master] section (or [main]) of puppet.conf: environmentpath = $confdir/environments

One directory environment also has to exist for it to be enabled.

I may send a pull request if I have the time to implement this in the near future. Thanks!

[alvagante]

That would be appreciated. Please keep it backwards compatible with less recent Puppet versions.