Fix various spelling mistakes

mod/admin.php

@@ -33,11 +33,11 @@ require_once 'include/items.php';
 /**
  * @brief Process send data from the admin panels subpages
  *
- * This function acts as relais for processing the data send from the subpages
+ * This function acts as relay for processing the data send from the subpages
  * of the admin panel. Depending on the 1st parameter of the url (argv[1])
  * specialized functions are called to process the data from the subpages.
  *
- * The function itself does not return anything, but the subsequencely function
+ * The function itself does not return anything, but the subsequently function
  * return the HTML for the pages of the admin panel.
  *
  * @param App $a

src/Database/DBA.php

@@ -821,7 +821,7 @@ class DBA
 	 * @param array $param parameter array
 	 * @param bool $on_duplicate_update Do an update on a duplicate entry
 	 *
-	 * @return boolean was the insert successfull?
+	 * @return boolean was the insert successful?
 	 */
 	public static function insert($table, $param, $on_duplicate_update = false) {
 

src/Model/User.php

@@ -644,7 +644,7 @@ class User
 	}
 
 	/**
-	 * @brief Sends pending registration confiŕmation email
+	 * @brief Sends pending registration confirmation email
 	 *
 	 * @param string $email
 	 * @param string $sitename