on libevent2 we need to wrap evbuffer_add with evbuffer_freeze/evbuffer_unfreeze. Not sure exactly why, probably because we're doing some evbuffer_enable/disable/enable-again. Retain compatibility with the custom libevent1 in base on OpenBSD.

Thanks to the fact that we're using a bigger buffer in the net process, and thanks to the way otto@' malloc works, it was easy to detect this off-by-one in a large page (RFC3089 in particular).

let's start an experiments: using LINE_TEXT instead of LINE_PRE_CONTENT for documents managed by the texplain parser. I never read much text/plain content until now, but by starting to use finger and gopher the amount of text pages is only bound to grow.