Updates to allow assigning URL paths to static pages upon creation and more!

When creating static pages you can now set a specific url for the page. If the user forgets to assign one it will automatically use the hyphenated version of the title they entered. Static pages resolve to these url paths. The 3 seeded pages (Home, About, and FAQ) also has their paths properly assigned when seeding.

@angaither 

PAGE SLUGS!
![url](https://cloud.githubusercontent.com/assets/105849/4279577/abfde954-3d22-11e4-90a8-69bc92ca3784.jpg)

CC: @barryclark @DFurnes 

Same as actual title; convenience column so I don't need to query the Pages table too to get the written title to output, for example, a list of page links in the Navigation.

Seemed useful for pages like the FAQ, where the path is /faq, but I can't know to capitalize all the letters for this specific link item.