PR: 1503
Submitted by: KISA
Reviewed by: Bodo Moeller

alloacted ASN1_STRING structure.

options. Add new streaming i2d (though strictly speaking it is BER format
when streaming) and PEM functions.

These all process content on the fly without storing it all in memory.

Remove unnecessary reference to EVP_MD_CTX in HMAC pkey method.

terms of new API.