DIRSTUDIO-959 (Exporting schemas as OpenLDAP files does not use proper escaping):
* Moved utilities to render ObjectClass and AttributeType to new SchemaObjectRenderer class
* Introduced two styles for rendering schema object: for usage in subschema subentry and for writing OpenLDAP like schema files
* Removed redundant schema object render implementations

git-svn-id: https://svn.apache.org/repos/asf/directory/shared/trunk@1545951 13f79535-47bb-0310-9956-ffa450edef68