Make user#show display comment history
Add navigation link to current user's comment history
Extract chronological scope
start guest can view posts
Allow guest to browse posts
User cannot create a post without a category
Create a category if none exist
Move resource above route in routes.rb
Change buttin to link in posts new
Remove extra newline
Merge branch 'lea-guest-can-browse-posts'

* lea-guest-can-browse-posts:
  Remove extra newline
  Change buttin to link in posts new
  Move resource above route in routes.rb
  Create a category if none exist
  User cannot create a post without a category
  Allow guest to browse posts
  start guest can view posts
  Extract chronological scope
  Add navigation link to current user's comment history
  Make user#show display comment history