Reorganize file structure.

src/_h5ai/.htaccess

@@ -1,3 +1,27 @@
 Satisfy all
-Order deny,allow
-Deny from all
+Order allow,deny
+Allow from all
+
+DirectoryIndex disabled
+
+<IfModule mod_autoindex.c>
+    Options -Indexes
+</IfModule>
+
+AddDefaultCharset utf-8
+
+<IfModule mod_mime.c>
+    AddCharset utf-8 .css .html .js .json .php .svg
+</IfModule>
+
+<IfModule mod_expires.c>
+    ExpiresActive on
+    ExpiresDefault                                      "access plus 1 month"
+
+    ExpiresByType text/html                             "access plus 0 seconds"
+    ExpiresByType application/json                      "access plus 0 seconds"
+
+    ExpiresByType text/css                              "access plus 1 week"
+    ExpiresByType application/javascript                "access plus 1 week"
+    ExpiresByType image/x-icon                          "access plus 1 week"
+</IfModule>

src/_h5ai/index.php

@@ -4,9 +4,9 @@ define('MIN_PHP_VERSION', '5.4.0');
 
 if (!function_exists('version_compare') || version_compare(PHP_VERSION, MIN_PHP_VERSION, '<')) {
     header('Content-type: text/plain;charset=utf-8');
-    echo '[err]  {{pkg.name}} requires PHP ' . MIN_PHP_VERSION . ' or later, but found PHP ' . PHP_VERSION;
+    echo '[err]  h5ai requires PHP ' . MIN_PHP_VERSION . ' or later, but found PHP ' . PHP_VERSION;
     exit;
 }
 
-require_once __DIR__ . '/../backend/php/class-bootstrap.php';
+require_once __DIR__ . '/private/php/class-bootstrap.php';
 Bootstrap::run();