Added Date to "Saved as Draft" State
Update the PublishDate on first Publish

If the PublishDate hasn't been set to the future.
Display a 'Modified' tag in the State column for modified pages
GridFieldBlogPostState: Made indentation consistant
BlogPost: onBeforePublish: Removed owner + added 'dbObject'
GridFieldBlogPostState: Added 'Modified' tag to timer state

and adjusted code spacing.
Merge pull request #19 from purplespider/modified-state

Display a 'Modified' tag in the State column for modified pages
Merge pull request #18 from purplespider/publish-date

Update the PublishDate on first Publish
Merge pull request #17 from purplespider/draft-status

Added Date to "Saved as Draft" State