fmt: mention that fmt.c does not perform hyphenation
reg: start with environment named "0"
reg: \n[.ev] for the current environment name
ren: allow scale indicators for arguments of .ps

Some old macro packages use ".ps 10p" instead of ".ps 10".
ren: allow .tl with no arguments
in: remove in_last[]
cp: handle conditional blocks with no spaces between .ie/.if and \{