Record a triplet of {start, data, end} for all HTTP data items.

This represents a regrettable uglification of the sourcecode, but
most of it compiles out to constants and the runtime benefits will
be worth it.

Generate H_FOO magic strings for all the headers we know about.
These strings have a length as first char and always ends in ':'.

Also genereate H_FOO format strings in VCL compiler.

Mandate (with assert) that header references happen using H_FOO strings.

Make number of allowed HTTP headers a compile time constant (32)
but make the workspace a run-time variable (4096).

Introduce new SHM tag for dumping aborted HTTP protocol requests.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@531 d4fa192b-c00b-0410-8231-f00ffab90ce4