Add default encoding of utf8.

[cgc]

was wondering if you'd be interested in restoring the previous default for getCodec.

[ashtuchkin]

Hi Carlos! Why do you think it is needed? What is your use case? I see something like this str = iconv.decode(buf) to be misleading.

[cgc]

the only compelling reason I've got is backwards compatability. in any case, I totally respect asking users to be explicit.

[ashtuchkin]

Yes, I think explicitness here is better for the users. Thank you for your efforts!