Animated transition on `window.history.back()`
Merge pull request #557 from artemave/patch-1

Animated transition on `window.history.back()`
Use plain `if/else` statements when there's no assignment.
Switch to `(function){..})()`.
Remove JSHint's `expr` rule.
Remove `devel:true` and use `window.console` instead.
Minor style changes.
Run `grunt`.