Introduce new folder type that does not allow SNS

Tricky issues can result from SNS in folders. Also, most of the time, it is very undesirable that SNS for folders are created. If SNS is allowed by the CND, it is not possible to avoid them in a clustered environment without locking. Locking is not an option.

Thus, we should introduce a new folder type, that does

1) Not allow SNS
2) Is orderable

After this, we should be able to consolidate hippostd:folder and hippostd:directory into this new folder type.

We should also introduce a jcr runner that can separately run, and uses Node#setPrimaryType(String name) to modify existing hippostd:folder and hippostd:directory into the new folder type : When however an SNS folder is found, the runner should log a warning with the location, and skip those folders. These can be done later on then

The CMS will most likely need some modifications, likewise for the HST