added "blog" component
added "blog" component related database records
added table "#__blog_items"
added item JTable
added items model
added items view
added item controller
added item form
added item model
added item view (basic)
added view toolbar
fixed content store bug

If we want to stroe HTML content, we need to add a filter "JComponentHelper::filterText" into form xml
added items controller
added items toolbar