remove all calls to: `self.log()`

* this method isn't documented
* it works when rules are evaluated using the addon built
  from the branch `js/eval/master`
  * the class `Base_Sandbox` has a method `log`
  * at runtime, the variable `self` refers to an instance of this class,
    and is in scope when `eval()` is executed

this is cheating :)

..but more importantly,

* `self` is no-longer accessible/valid
  when rules are evaluated using the addon built
  from the branch `js/Cu.evalInSandbox/master`