CLC-3565: gem rspec-its, be_true > be_truthy, be_false > be_falsey

https://jira.ets.berkeley.edu/jira/browse/CLC-3565

1. 'its' command removed from rspec 3 so we add rspec-its
1. 86 files changed but changes do not exceed:
  + be_true > be_truthy
  + be_false > be_falsey