Merge branch 'mg/diff-stat-count'

* mg/diff-stat-count:
diff --stat-count: finishing touches
diff-options.txt: describe --stat-{width,name-width,count}
diff: introduce --stat-lines to limit the stat lines
diff.c: omit hidden entries from namelen calculation with --stat

diff --cc Documentation/diff-options.txt
Simple merge

diff --cc diff.c
Simple merge

diff --cc diff.h
Simple merge