Fix wrong argument order when picking the Host header.

Fix wrong argument order for isprefix() when picking the Host
header. This caused the header to never be matched.

Fixes: #1383
Remove log record terminating null char before processing log lines.

Fix the end of log record pointer to not include the record
terminating null char. This caused the null to be part of the captured
fragments and sent to the output.

Fixes: #1382
Create .rst documentation from the vmod.vcc file.

This causes a change of syntax for the vcc file, it is however
very slight:  "Module", "Init", "Function", "Object" and "Method" needs
a "$" prefix, and the methods refer to the previous $Objecet without
the enclosing { }.

The first contiguous set of lines starting with "#" is treated as
a copyright notice, and emitted last, unless the first line is "#-"
Use weaker plain magic check for WS overflows to avoid recursive panics
Don't attempt to dump bad WS structs