Add initial files and templates for ps_emailalerts module

- Created LICENSE file for composer dependencies.
- Added autoload files: autoload_classmap.php, autoload_namespaces.php, autoload_psr4.php, autoload_real.php, and autoload_static.php.
- Initialized installed.json for composer.
- Added index.php and form templates for admin configuration.
- Implemented front-end templates for email alerts, including account management and product notifications.
- Included necessary headers and copyright notices in all new files.

modules/ps_emailalerts/mails/sk/productcoverage.txt

@@ -0,0 +1,13 @@
+
+[{shop_url}] 
+
+Dobrý deň, 
+
+Množstvo na sklade je momentálne menšie ako špecifikované
+minimum: {warning_coverage}.
+
+MOMENTÁLNE MNOŽSTVO NA SKLADE: {current_coverage} 		 
+
+{shop_name} [{shop_url}] powered by
+PrestaShop(tm) [http://www.prestashop.com/] 
+