dncp-00: Added keep-alive custom timer framework that looks sensible (but is perhaps over-complex?).
dncp-00: Typo fix or two.
dncp-00: Simplified keep-alive handling, and added own section for it.
dncp-00: Got rid of per-peer keep-alives (for now).
dncp-00: Removed header part from length of TLVs.
Some editing
Merge branch 'dncp-00-ka' into dncp-00