template: provide tp_write_htmlescape() it's like tp_htmlescape() but takes a size instead of a NUL-terminated string. Part of a larger diff that's ok tracey@

portable: template: use got_compat.h

gotwebd: move the buffering from the fastcgi layer to the template Reduces the indirection in fcgi.c, starts to make the struct template opaque, simplifies the template usage. All with a net negative :-) reads fine to stsp@ (thanks!)

template: adjust my address

import template ok tracey@