Fix Yum URL path for RedHat systems still using the PC1 collection

[coreone]

Currently, if you have a RedHat-based machine and you specify the PC1 collection, you get a yum repository configuration with the source set to:

http://yum.puppet.com/PC1/el/6/x86_64

However, the correct URL should be:

http://yum.puppet.com/el/6/PC1/x86_64

This PR fixes the source to use the correct URL if PC1 is the collection being used.

[puppetcla]

Waiting for CLA signature by @coreone

@coreone - We require a Contributor License Agreement (CLA) for people who contribute to Puppet, but we have an easy click-through license with instructions, which is available at https://cla.puppet.com/

Note: if your contribution is trivial and you think it may be exempt from the CLA, please post a short reply to this comment with details. http://docs.puppet.com/community/trivial_patch_exemption.html

[coreone]

I believe this was a trivial contribution as it was literally a copy/paste of the original code, and closely mimics previous code in the history, so this can pretty much be considered a code reversion.

As a side note to this process:

• The URL to the documentation should be updated to https://puppet.com/community/trivial-patch-exemption-policy as the one sent is a dead link
• The certificate on the CLA site has expired

[mihaibuzgau]

👍 Thanks, @coreone for the contribution