Merge branch 'maint'

* maint:
  help: improve text about automatically-distributed files
  refactor: split 'usage' subroutine in automake

diff --cc ChangeLog
Simple merge

diff --cc automake.in
index 7827680,d0d986e..517eea9
mode 100644,100755..100644
--- 1/automake.in
--- 2/automake.in
+++ b/automake.in

diff --cc doc/automake.texi
Simple merge

diff --cc tests/Makefile.am
Simple merge

diff --cc tests/Makefile.in
Simple merge

diff --cc tests/autodist-subdir.test
Simple merge

diff --cc tests/autodist.test
Simple merge