Merge branch 'mm/maint-hint-failed-merge'

* mm/maint-hint-failed-merge:
  user-manual: Document that "git merge" doesn't like uncommited changes.
  merge-recursive: point the user to commit when file would be overwritten.

diff --cc Documentation/config.txt
Simple merge

diff --cc Documentation/user-manual.txt
Simple merge

diff --cc merge-recursive.c
Simple merge