copyHeader() is redundant, we allocate a header and then copy the
non-pointer elements into it; we don't need to do this, because if we
just asssign rr.Hdr to something else we get the same result.
Remove copyHeader() and the generation and use of it in ztypes.go.
Make the reflection types a black list (these types use (or should use)
the tag 'size-xxx' in their struct definition.s
HIP, IPSECKEY, NSEC3, TSIG
All other types don't use reflection anymore.
* Return a pointer to the header when there is no rdata, this restores old
behavior. The rest of the conversion mostly hangs on getting size-hex
right, but then packStruct and packStructValue and the unpack variant
can be killed.
* Generate pack and unpack for all embedded types as well.
* Fix PrivateRRs, register an unpack function as well, when you register
a new PrivateRR.
* Add the tag octet, nsec, []domains and more to msg_helper.go
Add dns:txt parsing helper to prevent compile errors. This allows
us to generate all unpack/pack function.
Add pack to the RR interface definition and add this method to
PrivateRR.
We still use typeToUnpack to select which types don't use reflection.
Add function that dedups a list of RRs. Work on strings, which
adds garbage, but seems to be the least intrusive and takes the
last amount of memory.
Some fmt changes snook in as well.