UsersEntryHandler and GroupEntryHandler contain hardcoded users/groups home path and doesn't include system-rel-path

the constructor of SystemUsersEntryHandler looks as follows:

    public SystemUsersEntryHandler() {
        super("/jcr_root(/home/users/.*/)\\.content.xml");
    }

i.e. it hardcodes the path to the users home node to the Adobe AEM specific configuration. The default in Jackrabbit and Jackrabbit Oak is different (as you can see in http://svn.apache.org/viewvc/jackrabbit/oak/trunk/oak-security-spi/src/main/java/org/apache/jackrabbit/oak/spi/security/user/UserConstants.java?view=markup#l119).

instead of hardcoding the path it should be extracted from a configuration file in order to make the converter independent of Adobe AEM.

in addition: oak comes with an addition configuration option that defines the relative path below which all service users must be located (see http://svn.apache.org/viewvc/jackrabbit/oak/trunk/oak-security-spi/src/main/java/org/apache/jackrabbit/oak/spi/security/user/UserConstants.java?view=markup#l141). instead of traversing all user nodes (which may be quite a lot in a productive enviroment), it would be better to fix the pattern such that it is limited to the path, which is known to contain system users.

note: there is no validator in place that prevents other users from co-existing with system users.... so verifying the primary type would still be needed, but at least the system-user-handler would be limited to a usually fairly limited sub-tree of the whole user store.