Align chain of method calls
Add expectations for method call
Add guard clause for iterating
Add have_received_id and have_received_pw matcher

It supports receive counts of RSpec Mocks 3.0.
https://relishapp.com/rspec/rspec-mocks/v/3-0/docs/setting-constraints/receive-counts
Use `around` for entire test suite
Add respond tests for `color_<color>` methods
Fix bug `id` and `pw` are not cleared on fail

If user failed to login once, user can't login even if the inputs are
correct. Passing 'off' as id won't work, too.

This bug is introduced in 36101d8821e30948482eec1aac90082cbe474940.
Follow some Better Specs guidelines

http://betterspecs.org
Update documentation
Update documentation for models
Merge pull request #46 from yous/patch-rspec

Make test more strict
Merge pull request #47 from yous/patch-next

Add guard clause for iterating
Merge pull request #48 from yous/patch-login-bug

Fix bug `id` and `pw` are not cleared on login fail
Merge pull request #51 from yous/patch-documentation

Update documentation