fix(installer): revert untested changes

install.pl

@@ -22,16 +22,16 @@
 }
 
 sub get_filename {
-    my $file = shift || $_; # take the first argument or use default ($_)
-    $file =~ s/\.example$//; # remove '.example' at the end of filename
-    $file =~ tr/%/\//; # replace '%' with '/'
-    return $file;
+  my ($file) = (@_, $_);
+  $file =~ s/\.(?:example)$//;
+  $file =~ s!%!/!g;
+  return $file;
 }
 
 sub replace_file {
-    my ($src_file, $target_file) = @_;
-    system("rm", "-rf", $target_file); # remove the target file if it exists
-    link($src_file, $target_file); # create a hard link from src to target
+  my ($src_file, $target_file) = @_;
+  system("rm", "-rf", $target_file);
+  link_file($src_file, $target_file)
 }
 
 sub link_file {