o remove panic() in favor of err(3) and use err(3) functions
consistently throughout
o use stat(2)'s S_IS* macros rather than S_IF*
o [r]index -> str[r]chr
o convert some static buffers to dynamic ones
o use real tempfiles rather than reopening the same templates
o rename some functions that clash with libc
o convert wait_status from union to int and use wait(2) status macros
o fix multiple potential buffer overflows
o fix a few comments
o add $FreeBSD$
Reviewed by: nra, nectar (earlier version)
variable which is de-facto standard for MUAs.
Teach bomail to generate an in-reply-to header so threading MUAs and
mail->news gateways won't lose context.
While i was at it, removed two gratuitous standard violations for
functions starting with an underscore.
