[ci skip] Merge pull request #4986 from ka7/feature/spelling

Spelling fixes in comment blocks and docs
diff --git a/system/database/DB_query_builder.php b/system/database/DB_query_builder.php
index 56d2c0c..6b0e032 100644
--- a/system/database/DB_query_builder.php
+++ b/system/database/DB_query_builder.php
@@ -2441,7 +2441,7 @@
 	 *
 	 * Escapes identifiers in GROUP BY statements at execution time.
 	 *
-	 * Required so that aliases are tracked properly, regardless of wether
+	 * Required so that aliases are tracked properly, regardless of whether
 	 * group_by() is called prior to from(), join() and dbprefix is added
 	 * only if needed.
 	 *
@@ -2477,7 +2477,7 @@
 	 *
 	 * Escapes identifiers in ORDER BY statements at execution time.
 	 *
-	 * Required so that aliases are tracked properly, regardless of wether
+	 * Required so that aliases are tracked properly, regardless of whether
 	 * order_by() is called prior to from(), join() and dbprefix is added
 	 * only if needed.
 	 *