error out when searching a pack index which lacks a corresponding pack file
allow obstructed files skipped by 'got update' to be updated again
Commit e600f1246e15 breaks test_update_conflict_wt_rm_vs_repo_rm on FreeBSD
capsicum work: add fd field to got_repository, change got_packidx
tog: replace dead_view param of view_input() with view->dying