function getTriggers(trigger) {
        var show = (trigger || options.trigger || defaultTriggerShow).split(' ');
        var hide = show.map(function(trigger) {
          return triggerMap[trigger] || trigger;
        });
        return {
          show: show,
          hide: hide
        };
      }
Returns an object of show and hide triggers.

If a trigger is supplied,
it is used to show the tooltip; otherwise, it will use the `trigger`
option passed to the `$tooltipProvider.options` method; else it will
default to the trigger supplied to this directive factory.

The hide trigger is based on the show trigger. If the `trigger` option
was passed to the `$tooltipProvider.options` method, it will use the
mapped trigger from `triggerMap` or the passed trigger if the map is
undefined; otherwise, it uses the `triggerMap` value of the show
trigger; else it will just use the show trigger.