First two scenarios for no books found.
Add search feature
Steps added.
Add test for zero search results

Returns an empty array from the search method when no items match the
given search criteria
Extract Library class
Move Library into it's own file
Methods extracted from step definitions.
Move stuff into test_driver.rb
test_driver module, 1st
Add bookshelf and results libraries
tidy
FInished find book implementation
Add UIDriver modules

Extract explicit calls to Library to a driver module to separate it from
the step definitions.
Don't need book_count method on bookshelf.
Merge remote branch 'origin/master' into feature/no-such-book

Conflicts:
	features/step_definitions/steps.rb
Add an instance variable for Library collection

Replace the Library#collection method, with it's hard-coded library used
for testing, with an instance variable. The hard-coded library test
  collection is moved into the UIDriver.
merge the world!
Merge branch 'search/no_results' into team-solution

Conflicts:
	features/search.feature
	features/support/ui_driver.rb
Merge branch 'master' into feature/no-such-book

Conflicts:
	features/support/test_driver.rb
Merch duplicate step definition files

Two sets of step definitions had been created by teams working on the
same feature separate from each other. This commit merges the duplicate
files and deletes the spare.