o New macro POS_COPY to copy between term_pos_t.
o Add vtbuf_wth/vtbuf_htw helpers, to translate between screen coordinates and
circular history buffer location.
o Update vtbuf_iscursor to mark region selected by mouse.
o New helper vtbuf_flush_mark, to update regions where copy/paste mark changed.
o New method vtbuf_get_marked_len to get storage size for paste buffer.
o vtbuf_extract_marked fill (caller allocated buffer) with selected region data.
o Simplify mouse handler for copy/paste, and use vtbuf_flush_mark to update.
o New method vtbuf_scroll_mode, to help indicate Scroll mode by hiding cursor.
o Update header with new vtbuf methods.
o Add new vt_driver method vd_markedwin, to hold last window with selection.
o Enable paste support in core module.
Sponsored by: The FreeBSD Foundation
Pointed by: Claude Buisson <clbuisson@orange.fr> (Scroll mode indication)
o Join history buffer with screen buffer. Same type of things.
o Reimplement buffer as an array of rows. Make it circular, so no overflow
tracking.
o Implement VT_PROCESS mode. Locking of VT switching by owner process.
o Add debug and deadtimer sysctls. deadtimer - defaulting to 15 seconds, time
to wait process answer in VT_PROCESS mode, to do VT switch in case when
process hang.
o Implement later console attach.
o Fix (partially yet) keyboard allocation.
o Add drivers priority. Disallow to replace KMS driver with VGA.
o Add ability to resize terminals.
Sponsored by: The FreeBSD Foundation
