Feature migrations up/down (#270)

* Migrations up down

* Add forum model

* Syntactic sugar for db structure changes

* Refactor migrations with $up & $down

* Fix migrations upgrade and downgrade

+ Add option to disable auto migrate

* Add migrate:to command

Usage: php aac migrate:to x (x - database version)

* Show error when mail is not enabled

* Fixes regarding to init.php

* Add migrate command to manually upgrade db, incase auto migrate is disabled

* Fixed rest of the migrations

* Limit max version of database

* Don't allow minus number

* Option to clear specified plugin settings by name

* Version is required

* Fix PHPStan errors

* Unset $up after migration, to prevent executing same migration twice

* Add database version to output

* This is not needed

* Update 5.php

* Set database_auto_migrate on install

* Set blank & color only if current db version supports it

* Fix duplicate function declaration

system/migrate.php

@@ -17,6 +17,12 @@ if(fetchDatabaseConfig('database_version', $tmp)) { // we got version
 		$db->revalidateCache();
 		for($i = $tmp + 1; $i <= DATABASE_VERSION; $i++) {
 			require SYSTEM . 'migrations/' . $i . '.php';
+
+			if (isset($up)) {
+				$up();
+				unset($up);
+			}
+
 			updateDatabaseConfig('database_version', $i);
 		}
 	}
@@ -26,6 +32,12 @@ else { // register first version
 	$db->revalidateCache();
 	for($i = 1; $i <= DATABASE_VERSION; $i++) {
 		require SYSTEM . 'migrations/' . $i . '.php';
+
+		if (isset($up)) {
+			$up();
+			unset($up);
+		}
+
 		updateDatabaseConfig('database_version', $i);
 	}
 }