angular-ui/ui-router — pull request #861 by mike-tempest (2014-02-04 11:25:07+00:00)
Title: Added a .back method to ui-router, fixes #92

Adds $state.previous and $state.previousParams. Implements $state.back method
which wraps $state.transitionTo and can take an options object which is passed
through.

$state.previous and $state.previousParams are only updated when the transition
completes.