rename project: gotmarc -> smarc

pledge and unveil (via perl' OpenBSD::Pledge/Unveil) only on OpenBSD

dont "use lib ." in perl; resolve modules normally fix gotmarc(1) to set PERL5LIB when running in-repo however to load the right GotMArc.pm.

move mention of game of trees from source into the template

add search.html template msearchd will also make use of it.

move thrslice to GotMARC.pm and add it hidden in thread_header

link /search and add a form in the index pages

drop unnecessary unveil(".", "r") These programs don't need to read files in the current directory: GotMArc loads in memory some files at load time, at that point no other accesses to "." are needed.

dedup thread entry generation code

change GotMArc::parse to take the line instead of $_

make GotMArc::parse return an hash reference instead of a list of strings

set binmode utf8 for the page file handler avoids the "Wide character in print at ./mkindex line 152, <> line 2751" warnings.

fix last sender name/date in the index pick up the *latest* From/Date for the indexes, not what happened to be the last mail rendered in that thread. spotted by stsp@

mkindex: show the latest date/sender per thread

urlencode the mail/thread id reminded by semarie@, thanks!