Added default namespace when no schema support

The current implementation uses the schema name as namespace name.
Some platforms don't support schema's, but a namespace name still needs to
be present. Added namespace name 'default' when there is no default schema
name.

lib/Doctrine/DBAL/Schema/Visitor/CreateSchemaSqlCollector.php

@@ -107,8 +107,8 @@ class CreateSchemaSqlCollector extends AbstractVisitor
     {
         $namespace = $asset->getNamespaceName();
 
-        if ( !isset($namespace)) {var_dump(get_class($this->platform));
-            $namespace = $this->platform->getDefaultSchemaName();
+        if ( !isset($namespace)) {
+            $namespace = $this->platform->supportsSchemas() ? $this->platform->getDefaultSchemaName() : 'default';
         }
 
         if ( !isset($this->createTableQueries[$namespace])) {