Revert r36413 -- renaming of search files into 'search' subdirectory

The loss of specific names would create a visible name conflict; when you've got "MySQL.php" open, what the hell is it? Is it the DatabaseMySQL class? Some other random MySQL-related thing? Update.php is also confusing -- we have an update.php which is a command-line script.
Don't do these confusing names; there's no pressing functional need to move the files at all, but if you must move them at least keep their distinct names so I can find my code.

includes/AutoLoader.php

@@ -126,10 +126,10 @@ class AutoLoader {
 		'MimeMagic' => 'includes/MimeMagic.php',
 		'MWException' => 'includes/Exception.php',
 		'MWNamespace' => 'includes/Namespace.php',
-		'MySQLSearchResultSet' => 'includes/search/MySQL.php',
+		'MySQLSearchResultSet' => 'includes/SearchMySQL.php',
 		'Namespace' => 'includes/NamespaceCompat.php', // Compat
 		'OldChangesList' => 'includes/ChangesList.php',
-		'OracleSearchResultSet' => 'includes/search/Oracle.php',
+		'OracleSearchResultSet' => 'includes/SearchOracle.php',
 		'OutputPage' => 'includes/OutputPage.php',
 		'PageHistory' => 'includes/PageHistory.php',
 		'PageHistoryPager' => 'includes/PageHistory.php',
@@ -137,8 +137,8 @@ class AutoLoader {
 		'Pager' => 'includes/Pager.php',
 		'PasswordError' => 'includes/User.php',
 		'PatrolLog' => 'includes/PatrolLog.php',
-		'PostgresSearchResult' => 'includes/search/Postgres.php',
-		'PostgresSearchResultSet' => 'includes/search/Postgres.php',
+		'PostgresSearchResult' => 'includes/SearchPostgres.php',
+		'PostgresSearchResultSet' => 'includes/SearchPostgres.php',
 		'PrefixSearch' => 'includes/PrefixSearch.php',
 		'Profiler' => 'includes/Profiler.php',
 		'ProfilerSimple' => 'includes/ProfilerSimple.php',
@@ -158,18 +158,18 @@ class AutoLoader {
 		'Revision' => 'includes/Revision.php',
 		'RSSFeed' => 'includes/Feed.php',
 		'Sanitizer' => 'includes/Sanitizer.php',
-		'SearchEngineDummy' => 'includes/search/Engine.php',
-		'SearchEngine' => 'includes/search/Engine.php',
-		'SearchHighlighter' => 'includes/search/Engine.php',
-		'SearchMySQL4' => 'includes/search/MySQL4.php',
-		'SearchMySQL' => 'includes/search/MySQL.php',
-		'SearchOracle' => 'includes/search/Oracle.php',
-		'SearchPostgres' => 'includes/search/Postgres.php',
-		'SearchResult' => 'includes/search/Engine.php',
-		'SearchResultSet' => 'includes/search/Engine.php',
-		'SearchResultTooMany' => 'includes/search/Engine.php',
-		'SearchUpdate' => 'includes/search/Update.php',
-		'SearchUpdateMyISAM' => 'includes/search/Update.php',
+		'SearchEngineDummy' => 'includes/SearchEngine.php',
+		'SearchEngine' => 'includes/SearchEngine.php',
+		'SearchHighlighter' => 'includes/SearchEngine.php',
+		'SearchMySQL4' => 'includes/SearchMySQL4.php',
+		'SearchMySQL' => 'includes/SearchMySQL.php',
+		'SearchOracle' => 'includes/SearchOracle.php',
+		'SearchPostgres' => 'includes/SearchPostgres.php',
+		'SearchResult' => 'includes/SearchEngine.php',
+		'SearchResultSet' => 'includes/SearchEngine.php',
+		'SearchResultTooMany' => 'includes/SearchEngine.php',
+		'SearchUpdate' => 'includes/SearchUpdate.php',
+		'SearchUpdateMyISAM' => 'includes/SearchUpdate.php',
 		'SiteConfiguration' => 'includes/SiteConfiguration.php',
 		'SiteStats' => 'includes/SiteStats.php',
 		'SiteStatsUpdate' => 'includes/SiteStats.php',