VCLs to cold (if they're in "auto" mode).

"auto", "cold" or "warm".

Regularize the names in the generated code.
Pass VCL events to backends.

The VRT side of things still needs attention

varnishd.  (special because -j must always be the very first argument)

	root		-- you must be root
	user_varnish	-- system must have a "varnish" user
	group_varnish	-- system must have a "varnish" group

- As VRB_Cache returns -1 upon error, so should VRT_CacheReqBody
- 0 is a valid body size, so it shouldn't be used for signalling errors
- VRB_Cache should return number of bytes when already cached
- VRB_Cache: return -1 on insufficient bytes also

over it with vdef.h.

Confine __unused to include/vtree.h at the same time.