Added recognition of Scientific Linux

[jcpunk]

I'll confess I didn't see where 'on oel' was comming from, but this should at least get SL support started.

[ekohl]

oel is just an example of something in the RedHat osfamily, but the actual value of $::operatingsystem here doesn't really matter. This is also just compile time checks and no actual OS installations begin tested. That means I consider this mostly cosmetic. However, I do think SL is more likely to be used some I'd be fine with this.

[stbenjam]

Hi @jcpunk, thanks for the PR. I don't understand the goal of it though - this is our (admittedly limited) test suite for the puppet module.

Any non-Fedora, non-RedHat value is valid for the spec, be it SL, or OEL. We're not expressing support or any kind of preference here.

[jcpunk]

For the most part, I ran into http://projects.theforeman.org/issues/7882 and said, "I should look for anything else that snuck through on HEAD".

Since the OEL stanza was duplicated, I figured swapping it over to say SL was an easy way of trying to make sure the installer was ready for anything.

[stbenjam]

@jcpunk Ah I see, thanks - I didn't realize the OEL spec was duplicated. I've also got no problem with this then, thanks!

Regarding 7882, that is fixed in our git repositories and should go out with the next release - you can try on the nightlies today, or try the patch over at #41.

[ekohl]

Maybe my intention was to add SL then, but didn't complete it past copy-pasting. Thanks @jcpunk.