Prep Plugin for release on WordPress.org (#23)

* Update translation text domain
* Escape everything that should be escaped.
* Add nonce checks where needed.
* Sanitize all inputs.
* Apply Code style changes across the codebase.
* Correct many deprecation notices.
* Optimize load order of many filters.
* Add Proper Build script
* Use emojii flags
* Fix i18n deprecation  notice for translating too early
* Put all scripts in footer and load async

inc/managers/class-block-manager.php

@@ -56,7 +56,7 @@ class Block_Manager extends Base_Manager {
 			[
 				[
 					'slug'  => 'wp-ultimo',
-					'title' => __('Multisite WaaS', 'wp-ultimo'),
+					'title' => __('Multisite WaaS', 'wp-multisite-waas'),
 				],
 			]
 		);