What type of change is described by a git_diff_delta?
GIT_DELTA_RENAMED and GIT_DELTA_COPIED will only show up if you run
git_diff_find_similar() on the diff object.
GIT_DELTA_TYPECHANGE only shows up given GIT_DIFF_INCLUDE_TYPECHANGE
in the option flags (otherwise type changes will be split into ADDED /
DELETED pairs).
no changes
entry does not exist in old version
entry does not exist in new version
entry content changed between old and new
entry was renamed between old and new
entry was copied from another old entry
entry is ignored item in workdir
entry is untracked item in workdir
type of entry changed between old and new
entry is unreadable