Use PDO for MySQL queries (#8935)

Gut dbFacile
mres() now does nothing... could have some vulnerable queries, but most are ok

TODO
- [x] IRC client broke
- [x] Install broke

DO NOT DELETE THIS TEXT

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validate.php

@@ -138,11 +138,11 @@ if (!file_exists(Config::get('install_dir').'/config.php')) {
 
 
 // Connect to MySQL
-try {
-    dbConnect();
+\LibreNMS\DB\Eloquent::boot();
 
+if (\LibreNMS\DB\Eloquent::isConnected()) {
     $validator->ok('Database connection successful', null, 'database');
-} catch (\LibreNMS\Exceptions\DatabaseConnectException $e) {
+} else {
     $validator->fail('Error connecting to your database. '.$e->getMessage(), null, 'database');
 }