fix(client): transition from password reset confirmation to signin once reset is complete
fix(tests): Ensure all tests pass.

* Add front end tests for confirm_reset_password to ensure coverage.
* Update Selenium tests to ensure localStorage and sessionStorage state is cleared for the settings tests.
* In the selenium tests, use safeEval when clearing localStorage to ensure operation completes before continuing (this is what WD does too).
Merge pull request #832 from mozilla/issue-787-reset-password-flow

fix(client): transition from password reset confirmation to signin once ...

r+ - this is pretty awesome @zaach!