Merge branch 'develop' of github.com:halmai/CodeIgniter into db/init_exception

Author: narfbg

system/database/DB_driver.php

@@ -436,7 +436,7 @@ public function initialize()
 					$this->display_error('db_unable_to_connect');
 				}
 
-				return FALSE;
+				throw new RuntimeException('Database connection failure.');
 			}
 		}
 

user_guide_src/source/changelog.rst

@@ -11,6 +11,10 @@ Release Date: Not Released
 
    -  Added UNIX socket connection support to :doc:`Session Library <libraries/sessions>` 'redis' driver.
 
+-  Database
+
+   -  CI_DB_driver::initialize() throws a "Database connection failure." RuntimeException if couldn't connect to the database.
+
 
 Version 3.0.4
 =============