[Patternfly] Slight change to website navigation

[Matt Carrano]

Hi everyone,

I made a small change to the navigation on the PatternFly website that will only effect folks contributing work on the Wiki.  All links to pattern work in progress can now be found in the Contribute section: https://www.patternfly.org/contribute/  This seemed to make more sense and create more separation between the "published" content and items under development.  

All content should be unchanged, but wanted to make sure everyone knew where to find pages they are working on.  Let me know if you have any questions.

Thanks,

Matt