Typecast limit and offset in the Database Driver to integers. Fixes https://bitbucket.org/ellislab/codeigniter-reactor/issue/341/active-record-limit-function-have-sql#comment-597403
diff --git a/system/database/DB_active_rec.php b/system/database/DB_active_rec.php
index 0238c73..7bab729 100644
--- a/system/database/DB_active_rec.php
+++ b/system/database/DB_active_rec.php
@@ -870,11 +870,11 @@
 	 */
 	public function limit($value, $offset = '')
 	{
-		$this->ar_limit = $value;
+		$this->ar_limit = (int) $value;
 
 		if ($offset != '')
 		{
-			$this->ar_offset = $offset;
+			$this->ar_offset = (int) $offset;
 		}
 
 		return $this;