got 0.86

- fix race condition on NFS where log-message file's modify time may change
- fix gotd sending too large pack files in some cases
- support histedit fold operations which delete a file and then add it again
- make diffing files which changed into dirs and vice-versa possible
- handle files changing into directories during 'got update'
- add quoting to repository path sent to server for git-shell compatibility
- gotwebd: handle short reads and timeouts
- gotwebd: provide gotweb_render_page() entrypoint for all pages
- gotwebd: reply with non-200 HTTP status code on error