Porting over the rest of the decoding (RFC2047) and especially encoding
over to qbase64 is still pending, as it is a little trickier.
Change-Id: Id4740eb074a387aeea2cb94b781e204248530799
Reviewed-on: https://cl.tvl.fyi/c/depot/+/8582
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI