Merge branch 'perl-sub-protos' into maint

* perl-sub-protos:
  style: call perl functions 'like_this()', not '&like_this()'
  maint: use more perl subroutines prototypes in the automake script
  build: auto-generate perl subroutines prototypes for automake and aclocal
  refactor: rip module Automake::Language out of automake script

diff --cc automake.in
index 4bb9687,0df0965..d4c25c4
--- 1/automake.in
--- 2/automake.in
+++ b/automake.in
@@@ -5979,10 -5894,10 +5894,10 @@@ sub register_language (%
    # Update the pattern of known extensions.
    accept_extensions (@{$lang->extensions});
  
 -  # Upate the $suffix_rule map.
 +  # Update the $suffix_rule map.
    foreach my $suffix (@{$lang->extensions})
      {
-       foreach my $dest (&{$lang->output_extensions} ($suffix))
+       foreach my $dest ($lang->output_extensions->($suffix))
        {
          register_suffix_rule (INTERNAL, $suffix, $dest);
        }