Fix use of magit-find-file-hook
Turn on flyspell in Magit commit buffer

This was deactivated in git-commit-mode.el (0670764).
Use different git-commit-mode hook for orgstruct
Remove outdated work-around from Stan setup

Upstream no longer adds flymake to the mode hook (94f846c).
magit-annex: Unset default '--auto' flag
Unset magit-backup-untracked