Commit Briefs
make tmp dir location a compile-time setting and change gotweb's tmp dir
We are not sure whether a gotweb package can own /var/www/tmp on OpenBSD. Moving gotweb's tmp dir to /var/www/got/tmp sidesteps that issue.
rename commit to commit_id in gw_trans and fix setting gw_trans->commit_id from gw_index
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