1.15.0

- The LastFm podspec is now used by the example app as well
- Removed deprecated method:
    - (NSOperation *)performApiCallForMethod:(NSString*)method withParams:(NSDictionary *)params rootXpath:(NSString *)rootXpath returnDictionary:(BOOL)returnDictionary mappingObject:(NSDictionary *)mappingObject successHandler:(LastFmReturnBlockWithObject)successHandler failureHandler:(LastFmReturnBlockWithError)failureHandler;
- Added new method:
    - (NSOperation *)getEventsForLocation:(NSString *)location successHandler:(LastFmReturnBlockWithArray)successHandler failureHandler:(LastFmReturnBlockWithError)failureHandler;