Fixes since v1.9.1
------------------
+ * Documentation and in-code comments had many instances of mistaken
+ use of "nor", which have been corrected.
+
+ * "git fetch --prune", when the right-hand-side of multiple fetch
+ refspecs overlap (e.g. storing "refs/heads/*" to
+ "refs/remotes/origin/*", while storing "refs/frotz/*" to
+ "refs/remotes/origin/fr/*"), aggressively thought that lack of
+ "refs/heads/fr/otz" on the origin site meant we should remove
+ "refs/remotes/origin/fr/otz" from us, without checking their
+ "refs/frotz/otz" first.
+
+ Note that such a configuration is inherently unsafe (think what
+ should happen when "refs/heads/fr/otz" does appear on the origin
+ site), but that is not a reason not to be extra careful.
+
+ * "git update-ref --stdin" did not fail a request to create a ref
+ when the ref already existed.
+
+ * "git diff --no-index -Mq a b" fell into an infinite loop.
+
* When it is not necessary to edit a commit log message (e.g. "git
commit -m" is given a message without specifying "-e"), we used to
disable the spawning of the editor by overriding GIT_EDITOR, but