Remove "blog" tutorial (#7786)

[jtheuerkauf]

• Completely remove docs for the blog tutorial - caused odd page continuity
• Add tips for using bake to create structures and migrations
• Split database.rst so the Articles model is a separate page
• Minor grammar and phrasing updates

[markstory]

Thank You :tada:

[jtheuerkauf]

Glad to help, glad you liked the changes.