Don't symlink executables into bin/

If we do, "perlbrew use" doesn't work, because when it overrides your path
to "bin/:perls/VERSION/bin", the symlinks in bin/ will take precedence.

bin/ needs to be kept clean of "perl" commands for use to work.

There is one case left: "perlbrew switch /path/to/very/specific/perl"
"perlbrew use" still fails to work with that one.

We also included upgrade notes in the Changes file. We need to

   perlbrew init
   perlbrew off
   perlbrew switch version-you-want

to clean up all the old symblinks.

Signed-off-by: Pedro Melo <melo@simplicidade.org>

Changes

@@ -1,4 +1,7 @@
 NEXT:
+
+- UPDATE NOTES: you need to init, off and switch back to the version you want;
+- Fix "perlbrew use" to work even if we are switched to a specific version
 - Fix "perlbrew env" to use current version, sets PERLBREW_PERL and proper PATH
 - Feature: "perlbrew use" shows current version in use
 

lib/App/perlbrew.pm

@@ -491,10 +491,6 @@ INSTALL
         delete $ENV{$_} for qw(PERL5LIB PERL5OPT);
 
         if (!system($cmd)) {
-            if ($dist_version =~ /5\.1[13579]|git/) {
-                $self->run_command_symlink_executables($as);
-            }
-
             print <<SUCCESS;
 Installed $dist as $as successfully. Run the following command to switch to it.
 
@@ -607,12 +603,6 @@ sub run_command_switch {
     die "${dist} is not installed\n" unless -d "$ROOT/perls/${dist}";
     unlink "$ROOT/perls/current";
     system "cd $ROOT/perls; ln -s $dist current";
-    for my $executable (<$ROOT/perls/current/bin/*>) {
-        my ($name) = $executable =~ m/bin\/(.+?)(5\.\d.*)?$/;
-        my $target = "$ROOT/bin/${name}";
-        next unless -l $target || !-e $target;
-        system("ln -fs $executable $target");
-    }
 }
 
 sub run_command_off {