YKEmitter:initWithEncoding is not setting encoding

[chrislconover]

Despite its name, initWithEncoding is not setting the encoding property:

- (id)initWithEncoding:(NSStringEncoding)enc
{
    if((self = [super init])) {
        memset(&emitter, 0, sizeof(emitter));
        yaml_emitter_initialize(&emitter);

...

Needs

        encoding = enc;