added: guard-bundler gem
updated: gems
changed: destroy action shared example now creates 3 records instead of 7 for faster tests
reverted: Guardfile
removed: all lower_price and higher_price fields in all tables
removed: multiple traits merged into one trait, namely 'identifyable'
removed: lower_price and higher_price from seeds.rb
fixed: create action shared example failing sometimes with the same spec
enhanced: merged Phonable, Notable, and Ratable into a single concern Identifyable