Add BUILD_NUMBER to the security check in .htaccess

Change BUILD_NUMBER to be .ini format and add a big "do not edit" comment.

.htaccess

@@ -29,7 +29,7 @@
 # in your Apache2 config file before you uncomment this block or
 # you'll get an "Internal Server Error".
 #
-# <FilesMatch "(\.(class|fla|gitignore|inc|ini|sql|txt)|(README|LICENSE))$">
+# <FilesMatch "(\.(class|fla|gitignore|inc|ini|sql|txt)|(README|LICENSE|BUILD_NUMBER))$">
 #   Order deny,allow
 #   Deny from all
 # </FilesMatch>

BUILD_NUMBER

@@ -1 +1,6 @@
-52
+; This file keeps track of the build number for the "master"
+; branch of gallery3.  It's kept up to date by an automated
+; process.  You don't need to edit it.  In fact..
+;
+;     DO NOT EDIT THIS FILE BY HAND!
+build_number=52

modules/gallery/helpers/gallery.php

@@ -205,7 +205,7 @@ static function version_string() {
    * Return the contents of the BUILD_NUMBER file, which should be a single integer.
    */
   static function build_number() {
-    $lines = file(DOCROOT . "BUILD_NUMBER", FILE_IGNORE_NEW_LINES);
-    return $lines[0];
+    $result = parse_ini_file(DOCROOT . "BUILD_NUMBER");
+    return $result["build_number"];
   }
 }