maintain previous credis exception when throwing redis exceptions from resque

Author: chrisboulton

lib/Resque/Redis.php

@@ -142,7 +142,7 @@ public function __construct($server, $database = null)
 			}
 		}
 		catch(CredisException $e) {
-			throw new Resque_RedisException($e);
+			throw new Resque_RedisException('Error communicating with Redis: ' . $e->getMessage(), 0, $e);
 		}
 	}
 
@@ -245,7 +245,7 @@ public function __call($name, $args)
 			return $this->driver->__call($name, $args);
 		}
 		catch (CredisException $e) {
-			throw new Resque_RedisException($e);
+			throw new Resque_RedisException('Error communicating with Redis: ' . $e->getMessage(), 0, $e);
 		}
 	}