Sean Whitton] Closes:#856402.
Minor fixes:
+ * When source discrepancy involves file mode changes, report them
+ specially. Closes:#886442.
+ * In split brain mode, with unexpected diffs, print dgit view
+ commitid in suggested diff rune. (HEAD is wrong.) Closes:#886443.
+ * Fix message about missing quilt cache entry to refer to
+ HEAD rather than tree, since dgit needs a commit. Closes:#884646.
* Fix grammar error in 4.1 changelog entry. [Sean Whitton]
* Remove some whitespace "errors". [Sean Whitton]