Add admin notices

admin/includes/notice-install.php

@@ -0,0 +1,10 @@
+<?php
+if ( ! defined( 'ABSPATH' ) ) exit; // Exit if accessed directly
+?>
+<div id="message" class="updated sportspress-message">
+	<h3><?php _e( 'Welcome to SportsPress!', 'sportspress' ); ?></h3>
+	<p class="submit">
+		<a class="button button-primary button-hero" href="<?php echo admin_url('options-general.php?page=sportspress'); ?>"><?php _e( 'Settings', 'sportspress' ); ?></a>
+		<a class="button button-secondary button-hero" href="<?php echo add_query_arg('skip_install_sportspress', 'true' ); ?>"><?php _e( 'Skip setup', 'sportspress' ); ?></a>
+	</p>
+</div>