adds ruby to products fixtures.
adds product title length validation and test.
bare store controller scaffold.
iteration C1.
Iteration C2.
Iteration C3.
adds links to sidebar.
Iteration C4: test using assert_select.
8.5 caching.
Caching without an error message.

However: I fail to verify it's working.
Merge commit 'd1f81250d9ef672529c47a57ffd285dbaf6bb992'

Conflicts:
	app/models/product.rb
	app/views/store/index.html.erb
show date, time, in sidebar.
price formatted for the uk.
Cart scaffold (9.1).
Removes currency formatting play.
LineItem scaffold and Cart associations.

(Iteration 9.2).
Add to Cart button buggy.

Creates new cart with every button click.
adds blank line.
bugfix: new cart created on each click.
Visits to store index counter.