Fix PgsqlAdapter native types, default values.

* The native types array were missing 'real','bigint','smallint', 'double precision', 'decimal' and 'numeric'.  See: http://www.postgresql.org/docs/9.1/static/datatype-numeric.html
* Both 0 and the empty string "" are valid defaults but were not being recognized.  Changed to check explicitly for NULL defaults.

Author: Justin Painter

lib/adapters/PgsqlAdapter.php

@@ -101,7 +101,7 @@ public function create_column(&$column)
 
 		$c->map_raw_type();
 
-		if ($column['default'])
+		if (!is_null($column['default']))
 		{
 			preg_match("/^nextval\('(.*)'\)$/",$column['default'],$matches);
 
@@ -131,7 +131,13 @@ public function native_database_types()
 			'time' => array('name' => 'time'),
 			'date' => array('name' => 'date'),
 			'binary' => array('name' => 'binary'),
-			'boolean' => array('name' => 'boolean')
+			'boolean' => array('name' => 'boolean'),
+			'bigint' => array('name' => 'integer'),
+			'smallint' => array('name' => 'integer'),
+			'real' => array('name' => 'float'),
+			'double precision' => array('name' => 'float'),
+			'numeric' => array('name' => 'float'),
+			'decimal' => array('name' => 'float')
 		);
 	}