fix check for near vs latlon, represent bools as strings in request para...

Hi,

Thanks for putting this client code together!

I've had to make a couple of changes to venueExploreRecommendedNearByLatitude to get it working properly:

* (!near && !near.length) && (!latitude && !longitude) is the necessary check for the presence of near or latlon
* The boolean parameters openNow and sortByDistance were causing stringByAddingPercentEscapesUsingEncoding to blow up. Translating the booleans to the expected strings in the parameter dictionary fixes this.